To counter the German invasion of Crete, Cunningham split his fleet into several Forces, which would act independently to intercept German sea transports. After German paratroopers landed on Crete on 20 May, "Gloucester" was assigned as the command ship of Force B and tasked with interdicting any efforts to reinforce the German forces on the island. Force B was ordered on a night patrol between Cape Elephonsi and Cape Matapan but encountered no enemies and joined up with Rear Admiral Rawlings' Force A1 on the morning of 21 May. A German and Italian convoy was sighted by allied reconnaissance later that day and Forces B, C and D were ordered to intercept and engage, with Force D making contact at 23:30.