Whose ships sank where?

Wikipedia keeps a remarkable list. For almost every year from the 1740s to 1945, and for every month from 1820, volunteer editors have written up the ships that were wrecked, foundered, burnt, captured or sunk, mostly from the shipping columns of Lloyd's List and the newspapers. Each entry gives the ship's name, the flag she sailed under, and a line on what happened and where.

I read all 236,326 entries, took the place each one names as the place of loss, and kept the 106,550 that put the wreck in a European sea: from the Arctic coast of Norway to the Black Sea. That lets me ask a simple question with a picture for an answer. In each stretch of sea, whose ships were lost?

The short answer is: the British, almost everywhere, until the twentieth century. But the record is a British one, built from British sources, and the more interesting story is in the exceptions: the seas and coasts, and the decades, where other flags take over.

01 · The mapEvery sea, every flag

Each donut gathers the wrecks in one square of the map grid, and its slices are the flags. Zoom in and the squares get smaller. Pick an era to see how the mix changes, or pick one flag to see only that nation's losses. Tap a donut for the ships inside it.

02 · Sea by seaThe British seas, and the mixed ones

Group the wrecks by sea and the pattern is plain. In the Irish Sea and its approaches, 89% of the 22,329 wrecks were British. In the North Sea it was 74%, and in the English Channel 70%. These were the home waters of the world's largest merchant fleet, and the waters Lloyd's List watched most closely.

Further out, the mix opens up. British ships were still the largest group in the Baltic (41%), the Mediterranean (39%) and the Black Sea (36%), but alongside German ships in the Baltic (22%), Italian ships in the Mediterranean (19%) and Russian ships in the Black Sea (26%). Two seas break the rule outright. In the Bay of Biscay the French flag leads, with 38% against 30% British. In the Norwegian Sea and the Arctic, German ships lead with 31%, and 88% of those German wrecks date from the Second World War.

One way to put a number on the mix is the "effective number of flags": the number of equally common flags that would give the same chance that two wrecks picked at random share a flag. The Irish Sea scores 1.24, close to a single flag. The Kattegat and Skagerrak, the narrow seas between Denmark, Norway and Sweden through which all Baltic trade passed, score 4.63, the most cosmopolitan of the ten, with the Mediterranean close behind on 4.55.

03 · Over timeFrom the age of sail to the world wars

The British share was highest during the long wars with France: 77% of placed wrecks from 1793 to 1815, and 81% in the five years from 1810. It stayed above 70% through most of the nineteenth century. Then it fell. In the First World War it was 49%, between the wars 41%, and in the Second World War 30%.

The wars rearrange the picture. In the First World War, German submarines sank neutral ships as well as Allied ones, and Norway, neutral but with one of the world's largest merchant fleets, lost heavily: Norwegian ships were 10% of placed wrecks in 1914 to 1918, against 4% in the half century before. French (10%) and Italian (7%) shares rose too.

In the Second World War the largest flag is German, at 33%: minesweepers, patrol boats, U-boats, transports and merchant ships lost from the Arctic to the Black Sea, 71% of them under a naval ensign. The most common sea for those German losses was the Mediterranean (545), then the North Sea (505) and the Baltic (501).

04 · Off whose coast?Home waters and foreign shores

Most of the wrecks lie off Britain and Ireland: 65% of all those placed. Off the coasts of other countries, the British flag is still the most common on 13 of the 18 coasts with at least 400 wrecks. Off France, 39% of wrecks were British and 32% French. Off Spain, 49% were British and 12% Spanish.

The exceptions are telling. Off Germany, German ships lead (45%), and off Italy, Italian ships (38%). Off Norway the Norwegian flag leads (32%) but German ships are close behind (30%), 79% of them lost in the Second World War. German ships also lead off Poland, the old Prussian Baltic coast (55%), and Italian ships off Tunisia (35%).

05 · LimitsWhose record is this?

• It is a British record. The lists were built mostly from Lloyd's List and British newspapers. They saw British ships, British coasts and the ports British ships used far better than a Swedish schooner lost in the Gulf of Bothnia or a Greek caique in the Aegean. The British share here is a share of the record, not of all the ships lost. The pattern across seas and over time is more trustworthy than any single share.
• Coverage changes. Some eras are written up in much more detail than others. The monthly lists from 1820 are far fuller than the yearly lists before them, the years 1919 to 1938 are thin (161.2 wrecks placed a year, against 782.5 from 1816 to 1913), and the world wars, drawing on naval loss records, are full. I compare shares, not counts, for this reason.
• Place is the place named. I put each wreck at the first specific place its description links (a sandbank, headland, port or island), not at the exact spot. Where the list gives coordinates, I used those. A wreck "40 miles off" a headland sits on the headland; one more than 60 nautical miles off is left out. This is fine for squares of a degree or so, not for finding a wreck.
• Flags are flags. A ship's flag is where she was registered, not where her crew or owners came from. I merged states across time (Prussia and the Hanseatic cities into German, Sardinia and the Two Sicilies into Italian, Denmark-Norway into Danish), and the merge list is in the code.
• Lost, not always sunk. The lists include ships driven ashore and later refloated, captured, burnt or damaged. I kept every entry, as the lists do.