Jun'yō was a Hiyō-class aircraft carrier of the Imperial Japanese Navy (IJN). She was laid down as the passenger liner Kashiwara Maru (橿原丸), but was purchased by the IJN in 1941 while still under construction and converted into an aircraft carrier. Completed in May 1942, the ship participated in the Aleutian Islands Campaign the following month and in several battles during the Guadalcanal Campaign later in the year. Her aircraft were used from land bases during several battles in the New Guinea and Solomon Islands Campaigns.

The Naval Battle of Guadalcanal, sometimes referred to as the Third and Fourth Battles of Savo Island, the Battle of the Solomons, The Battle of Friday the 13th, The Night of the Big Guns, or, in Japanese sources, the Third Battle of the Solomon Sea , took place from 12 to 15 November 1942 and was the decisive engagement in a series of naval battles between Allied and Imperial Japanese forces during the months-long Guadalcanal campaign in the Solomon Islands during World War II. The action consisted of combined air and sea engagements over four days, most near Guadalcanal and all related to a Japanese effort to reinforce land forces on the island. The only two U.S. Navy admirals to be killed in a surface engagement in the war were lost in this battle.