LAC (Library & Archives Canada, formerly National Archives of Canada) has the Diaries of Canadian Prime Minister William Lyon Mackenzie King online as a searchable database.
Using various search terms I was able to find entries for ships and passengers and voyages that King took. Many American as well as Canadian names appear in these diaries.
For instance, one 'hit' on the search terms "Passenger AND Ship" took me to the following entries for a voyage he was taking. Below is just a brief excerpt from the diary entries for those few days, which I've outlined just to give you the idea of what can be found:
Sept. 27/99. Mentions he sailed 'out of Boston" at 4:30 pm while bugles played Auld Lang Syne.
Sept. 28, 1899 Mentions a Mr. Street, a manufacturer in Beford and his little boy; Mr. Clough, connected with telephone work in Providence; Mr. Sturmay of Coventry England
Sept. 29, 1899: Mentions a Boston family named Bossom, Mr. W. Evans Darby, Mr Barry the first Officer, Mrs. Campbell.
Sept 30, 1899 On the Atlantic Ocean en route to England.Speaks in detail of a young girl, 25 years old, who died on board and was buried at sea
Oct. 1, 1899. He mentions various passengers, including
Miss Welder, Miss Minshall, Miss Saunders, Miss Clough
a 'little girl' Pauline Bossom (presumably of the Boston family mentioned earlier)
Minshall of Bristol England
Mr. Street, Mr. Callender of Adam Black and Co. Publishing House in London Eng; Mr. Morton
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