Find Canadians in new Findmypast UK and US Military Records

British Armed Forces, First World War Soldiers' Medical Records

There are 17,406 entries with corps "Canadians" and 752 "Canadian" in this British collection.

With over 36,000 additions from the (UK) National Archives record group MH106 (War Office: First World War Representative Medical Records of Servicemen), there are now 1,309,121 records available to search in this collection.
The originals are two-page registers. Optional search fields are the first name(s), last name, admission year, birth year, death year, piece, service number, rank, corps and, hospital. Initials are more common than the first names.
There's a browse capability for piece and hospital. The hospitals included are: 14th, 18th, 19th, 28th, 51st, 66th, 139th, 149th, Field Ambulance; 31st Ambulance Train; Nos 3, 11, 31, 34, 82 Casualty Clearing Station; No 34 Combined Casualty Clearing Station; Nos 34, 39 Combined Clearing Hospital; 2, 28, 85 General Hospital; 4th Stationary Hospital; Catterick Military Hospital; County Of Middlesex War Hospital At Napsbury; Craiglockhart Hospital; Hm Hospital Ship "Assaye".
The images indicate the nature of injuries or disease, dates of admission a discharge where they were treated, service details and occasional additional notes.
I noticed a number of entries for "coolies" of the Chinese Labour Corps. Many had no name entered.

United States, Official Army Register 1861-1865
Thousands of PDF images of official army registers created by the United States Adjutant General’s Office to uncover details of volunteer force service in the United States Army between 1861 and 1865. You can search by name but need to look at the PDF register for an individual's information — rank, name and enlistment date.
Ancestry, MyHeritage, and the Internet Archive all have versions of these records, helpful given the hit and miss nature of OCR.

United States, Massachusetts: Index Of Casualties, World War II
A collection of more than 9,000 records compiled by the Adjutant General of the Commonwealth and held by the Massachusetts Archives. Transcripts include rank, death date, death place, additional notes and a link to an image of the original document.

PERiodical Source Index Update
Over 6,000 new images have been added this month. These new additions add additional years for the Saint Louis Catholic Historical Review, Daughters of the American Revolution Magazine and the Friends Historical Society Journal