He was the fifth head football coach at Boston College, serving for four seasons between 1897 and 1901 and compiling a record of 16–16–2.

In 1922, Dunlop was residing in Boston, working as a real estate, mortgage and insurance broker.

[1] He was married to Alice Lillian Hall, whom he wed on October 25, 1899, and had two children, Lydia and John William Jr..

He later entered in a partnership with Stephen W. Sleeper, a fellow Harvard alumnus, to form the real estate firm Sleeper & Dunlop.

This biographical article relating to a college football coach first appointed in the 1890s is a stub.