Death in Office of United States Presidents

Death in Office of United States Presidents
Not only is an inaugural of a US president a collectible subfield of philately, but a term that is cut short is also. There have been nine presidents that did not finish their term of office. The reasons have been death due to illness, death due to assassination, or a retirement. Death covers of presidents are defined as a postal cover that is given a US postmark on the day of death of that president. A cover that is most highly prized would be one posted in the city of death, the city of birth, or Washington, DC. Thus death covers are very similar to inaugural covers.
Below is a list of the presidents and their day of death or early-retirement. The city of death is written after it. Be sure to look out for such covers since the pre-Roosevelt ones are quite rare and are without cachets indicating what they are. Hopefully you will find this list useful.

Harrison - April 4, 1841 - Washington, DC
Taylor - July 9, 1850 -Washington, DC
Lincoln - April 15, 1865 -Washington, DC
Garfield - September 19, 1881 -Washington, DC
McKinley -September 14, 1901 -Buffalo, New York
Harding -August 2, 1923 - San Francisco, California
Franklin - Roosevelt April 12, 1945 -Warm Springs, Georgia
Kennedy - November 22, 1963 - Dallas, Texas
Nixon -August 9, 1974 - Washington, DC (retirement)