The Sound Toll Registers (STR) are the records of the toll levied by the kings of Denmark on the ships passing through the Sound, the main strait connecting the North Sea and the Baltic Sea. For centuries, the kings’ bureaucrats administered this Sound Toll – Øresundstolden in Danish – in the small town of Helsingør, north of Copenhagen, where the strait is at its narrowest. The accounts of the toll have been preserved for intermittent years between 1497 and 1573, and practically entirely for the period from 1574 to 1857, when the Sound Toll was abolished. They cover about 300 of the 360 years between 1497 and 1857. The Sound Toll Registers – or Øresundstoldbøgerne – contain information on about 1.8 million passages. They are stored by the Danish National Archives in Copenhagen, where more than 700 volumes occupy about 60 meters of shelf space.

E. Gøbel, ‘The Sound Toll Registers Online project’, International Journal of Maritime History XXII:2 (2010) 305-324, there 305-308.

The information the kings’ bureaucrats entered in the registers for each ship’s passage was initially limited to the passage year, the name of the shipmaster, his place of residence, the toll amount paid and, when relevant, the toll amount paid for any cargo of wine. Information increased with the gradual introduction of additional tolls in the course of the centuries. It reached its more or less definitive form by the eighteenth century, when for each individual passage, both westward and eastward, the STR contain the declaration date, the name of the shipmaster, his place of residence,

There is a protracted historiographical discussion concerning the question if the STR actually list the shipmasters’ places of residence. The – Danish – wording in the source is, for example: Willem Blocker af Horn. It is our interpretation that – generally – the shipmaster lived in the place mentioned – in this case Hoorn. Some, however, have argued that the toponym refers to the homeport of the ship. Boon discusses the matter briefly in P. Boon, ‘Dutch connections to Scandinavia. The case of the West Frisian seaman abroad and at home’, in: M. Guldberg, P. Holm and P.K. Madsen (eds.), Facing the North Sea. West Jutland and the world (Esbjerg 1993), 87-101, there 95-98.

The STR are well known as one of the great serial sources of early modern history and the only one with rich and detailed information on European shipping and trade that spans a period of four centuries. They are a central source for social, economic and maritime history on all levels: global, European, national, regional and local.

Scheltjens, Veluwenkamp and Van der Woude, ‘A closer look’, 2.

Sound Toll Registers Online was initiated in 2006, by a project team from Tresoar and the University of Groningen, to improve access to the data included in the Sound Toll Registers.

Jan Willem Veluwenkamp (University of Groningen) and Siem van der Woude (Tresoar) managed the project. George Welling (University of Groningen) designed the database in the application phase. Douwe de Vries (then Director of Tresoar) and the late Rienk Wegener Sleeswijk encouraged and supported us.

In 2013, the cooperation with Breed was ended by mutual agreement. One of the reasons was of a financial nature, due to the unexpected workload required. In the years from 1633 to the nineteenth century, the information for each individual passage was recorded in one entry in the original Sound Toll Registers and, consequently, was entered in one record of the database. However, when Breed began to work on the registers from the years before 1634, it became clear that, in those years, it often occurred that the information for an individual passage was recorded in several entries in the STR and, consequently, had to be entered in several records in the database. This meant that to enter the data for the 300,000 passages that remained at that moment and to complete the database, an estimated 700,000 entries had to be completed. Since we had no budget for that, we had to organize the data entry in another way.

We turned to volunteers. To facilitate this, we contracted the Meertens Institute to create a data entry application, which allowed participants with a laptop and internet connection to work from home. In October 2013, a few volunteers began entering data and testing the system live.

Volunteers Siep Maat, Klaas Dantuma and Anneke Westerhuis did excellent work at that stage.

Sound Toll Registers Online includes for each passage

More precisely: for each STR entry. As discussed in the main text, passages were often recorded in more than one entry in the STR before 1634.

The data was entered into the database in the Danish language as used in the original source, including all early modern spelling variants to avoid contamination by premature interpretation. The spelling variations of personal names, geographical names, commodity names, measures and weights are almost without limit. Obviously, standardized spelling facilitates data analysis, but so far we have only standardized the spelling of the geographical names, while preserving the original input in the database and keeping it accessible there.

George Welling (University of Groningen) and Frank Bosmans (Tresoar) standardized the geographical names.

The database has four basic tables: passage, cargo, taxes and images. The passage table basically contains one record for each passage, including fields for the date and the shipmaster’s name and place of residence. It does not contain fields for the cargo and the ports of departure and destination, as many ships carried several commodities and the ports of departure and destination could differ per commodity. Accordingly, the cargo table contains per passage records for each commodity mentioned there, including fields for the commodity’s ports of departure and destination and for the tax paid per commodity. The separate taxes table contains records with fields for the tax or, in many cases, the several taxes levied per passage. The images table contains records with a field that connects the passage record with the scans of the relevant folio of the original source. The four tables are connectable by a common identity field.

STRO is essentially an instrument for historical research. It allows one to make all conceivable cross tabs and to carry out any statistical analysis.

Welling and Bosmans also designed the database.

The Sound Toll Registers are an extremely valuable source, but their sheer volume and detail make them virtually impossible to handle. It was in their effort to make the STR more suitable for researchers that Ellinger Bang and Kort produced the Sound Toll Tables (STT). As mentioned above, historians have indeed preferred using the STT to the STR. Accordingly, the STT have had enormous significance for historical research.

The importance of the STT, however, should not conceal their shortcomings. These limitations have been extensively discussed in the historiography.

See, for example: Gøbel, ‘The Sound Toll Registers Online project’; P. Jeannin, ‘Les comptes du Sund comme source pour la construction d’indices généraux de l’activité économique en Europe (XVIe-XVIIe siècle)’, in: P. Jeannin, Marchands du Nord. Espaces et trafics à l’époque modern (Paris 1996) 1-62; A.E. Christensen, ‘Der handelsgeschichtliche Wert der Sundzollregister. Ein Beitrag zu seiner Beurteilung’, Hansische Geschichtsblätter 59 (1934) 28-142; E.F. Heckscher, ‘Öresundsräkenskaperna och deras behandlings’, Historisk Tidskrift (1942) 170-186.

The unwieldiness of the STR and the limitations of the STT were among the reasons we built STRO. That does not mean that STRO is without intricacies or that it can be used thoughtlessly. It should be handled with care and with an understanding of its potential and its limitations. The individual researcher must be aware of these when using it. A few remarks explaining some of the complications of the STR and STRO offer clarification.

The Sound Toll Registers are a fiscal source. The Danish bureaucrats kept them not to produce statistics for future researchers but to give an accounting of the toll they levied to the king. The STR have been the subject of extensive source criticism. The discussions amount to three main concerns about their reliability. First, there were other routes from Western Europe to the Baltic Sea area, including the ones through the Little Belt and the Great Belt, the overland route, the sea route to Russia via the North Cape and, from 1784 on, the Schleswig-Holstein Canal. Although each of these routes may not have offered a serious alternative to the Sound, taken together they should not be omitted from the analysis of trade flows.

Hardly anything is known about the traffic through the Little Belt except that this strait was hard to navigate because of its winding channels and strong currents, and using it implied a long detour for ships sailing to and from the Baltic Sea.

Gøbel, ‘The Sound Toll Registers Online project’, 319-320. Gøbel mentions that toll registers of the Little Belt have been preserved for the years 1816-1857; Jeannin, ‘Les comptes du Sund’‚ 12.

The second concern about the STR’s reliability involves fraud. This did not mean stealing through the Sound without paying the toll. The chance of success in this respect was very low, as officials observed and guarded the strait from Kronborg castle and with the royal guard ship cruising it. It is widely accepted that all ships that sailed through the Sound in the years covered by the STR were recorded. Shipmasters, nevertheless, certainly evaded payment of part of the toll due by making false declarations of the commodities. Clearance was based on the ships’ documents, such as the bills of lading, though the customs officers were entitled to search the ships. Obviously, this did not stop all shipmasters from trying their luck. Comparison with other sources, especially customs accounts from individual ports – the dependability of which is incidentally problematic, too – has shown that the information on cargoes in the STR is generally correct but not complete.

Gøbel, ‘The Sound Toll Registers Online project’, 319-321.

A third reason that the STR must be handled with care is the fact that sometimes parties were exempted from paying the toll. This applies to Danish ships and goods throughout the period and to Swedish vessels and commodities between 1650 and 1710.

Jeannin, ‘Les comptes du Sund’, 39-40.

STRO is an interpretation of the STR and not compiled as a source edition. It is constructed as an organic historical source fitted into a much more sterile database. With the source criticism of the STR in mind, the researcher also needs to understand the details of STRO. Only the most obvious of these can be briefly discussed here.

First and foremost, we have only entered the STR toll collection entries proper into the database and have omitted a large quantity of additional information. This mainly involves the recurrent introductory, accounting and justifying texts the toll officials noted. In addition, as the database has a strict format, we could not include the extra information the officials sometimes added in the passage entries. This information is diverse. It may involve the owner or addressee of part of the cargo, a ship having been stranded, or a rotted part of the cargo. In order not to completely lose sight of that information, we have, as a rule, put a reference in the field ‘opmerking bron’– ‘remark on the source’. This reference is often worded only as ‘stuk Deense tekst’ – ‘piece of Danish text’ – with no further details.

Not all entry problems were solved after extra information had been dealt with – or disposed of – in this way. The STR developed organically over more than three and a half centuries so that their form and precise content changed and varied from one period to the other. This means that we had to handle all kinds of peculiarities to fit the content of the STR entries proper into the database. The three most conspicuous examples are connected to the recording of the value of a commodity, the formulas ‘giør’ and ‘er’, and references in one STR entry to another. We briefly discuss them in the following paragraphs.

Usually, the STR record commodities – the components of the cargo – by stating the quantity, the unit of measure and the commodity, e.g., 60 læster rug (60 lasts of rye).

www.soundtoll.nl, record 152363, 25 August 1783.

In approximately less than 0.6 percent of the STR entries, there is a reference to another entry, characterized by the term ‘Vide Fol.’ and followed by the relevant folio number and passage number.

For example www.soundtoll.nl, record 119865, 21 August 1783.

Finally, despite all efforts to maximize correct reproduction of the content of the STR entries, it is inevitable that the database contains many small errors and perhaps a few omissions. However, errors in the original spelling hardly affect the substance of the information. In other cases, the user will have to rely on their critical mind and knowledge to avoid mistakes and errant interpretations. We are confident that the quality of the information in the database allows all queries to produce accurate results. Moreover, the digitized originals in the database allow researchers to verify the information.

Before STRO was available, historians used the STR and the STT mainly to produce statistics of rather generally categorized ship movements and commodity flows. Now, STRO allows the researcher to exploit easily the richness of the STR to a depth that used to be hardly attainable. Analyses that were previously almost inconceivable can now be carried out quickly and easily, and the STR’s different dimensions – particularly place, time, cargoes and shipmasters – can be instantly combined in all the detail of the original source and on every conceivable level of aggregation.

Most evident is the utilization of STRO for the research of basic structures and developments of trade and transport of individual commodities or commodity categories on a local, regional, national or global level. An early publication exploring these possibilities discusses the flow of coffee to the Baltic region countries in the eighteenth century, including the breakdown into the countries from where the carrying ships left and where they were destined.

M. Draper and J.W. Veluwenkamp, ‘Sound Toll Registers Online and the eighteenth century Baltic coffee commerce’, Groniek 200 (2014) 279-294.

STRO is a gold mine for detailed in-depth exploration and analysis. Micro-historical research employing STRO can focus on many things. A single port of departure or destination, one place of residence, however big or small, a route, a commodity, even the itineraries of any individual shipmaster may be the starting point for innovative research and contribute to the social and economic history of the early modern and modern periods. One example is an article presenting a methodology for estimating the volume of timber shipped from the Baltic Sea area to Spain in the period 1670-1806.

N. Gallagher, ‘A methodology for estimating the volume of Baltic timber to Spain using the Sound Toll Registers: 1670-1806’, The International Journal of Maritime History 28:4 (2016) 752-773.

Similarly, STRO can also help gauge the impact of political decisions and developments on international trade, revealing short-term crises and spikes in commodity flows and facilitating studies on the impact of trade blockades, port sieges, war and the threat of war on transport through the Sound. Indeed, practically any analysis of traffic using STRO will show the effects of war, with the French Revolutionary and Napoleonic Wars standing out.

This is illustrated by J.W. Veluwenkamp, ‘Pekelder schippers in de achttiende eeuw. Van turfvaart naar kustvaart’ Jaarboek Noordelijk Scheepvaartmuseum 2016 (Groningen 2017) 25-31.

STRO is not a research agenda but a research instrument which is being used already. Examples are provided by two edited books, which were published in 2018 and 2019.

Veluwenkamp and Scheltjens (eds.), Early modern shipping and trade; M.-W. Serruys (ed.), Proceedings of the sixth Sound Toll Registers Online conference, Antwerp, Belgium(22-23 October 2015) (Antwerp 2019).