With the outbreak of World War I, he attempted to maintain the country's neutrality, though he tended to support the Allies, whose colonial territories in Africa surrounded Liberia.

Realizing that their complaints were in vain, the Germans sent a submarine to attack the city in 1917, forcing the reluctant Howard to side with the Allies and declare war on Germany.

In 1915, the coastal Kru people, who had long resisted Monrovia's authority, rose in rebellion, declaring their loyalty to Great Britain and demanding annexation by Crown Colony of Sierra Leone.

In response, the United States diverted the USS Chester to Africa en route home from Turkey to help quash the uprising.

Realizing that their complaints were in vain, the Germans sent a submarine to attack the city in 1917, forcing the reluctant Howard to side with the Allies and declare war on Germany on 12 January 1918.

Whenever the British and French seemed intent on enlarging at Liberia's expense the neighboring territories they already controlled, periodic appearances by U.S. warships helped discourage encroachment, even though successive American administrations rejected appeals from Monrovia for more forceful support.