Second Samoan Civil War Ensign John R. Monaghan (26 March 1873 – 1 April 1899) was an officer in the United States Navy.

Promoted to the rank of Ensign in July 1897, he was next assigned to the monitor Monadnock and gunboat USS Alert (AS-4), both of which operated along the West Coast of the Americas.

When his unit's leader, Lieutenant Philip Lansdale, was wounded, Ensign Monaghan seized a rifle and attempted to rescue the injured officer.

The official report of the action stated: "The men were not in sufficient numbers to hold out any longer, and they were forced along by a fire which it was impossible to withstand.

The inscription reads: "During the retreat of the allied forces from the deadly fire and overwhelming number of the savage foe, he alone stood the fearful onslaught and sacrificed his life defending a wounded comrade Lieutenant Philip V. Lansdale United States Navy.