Guadalcanal campaign
As the Japanese troops gathered west of the Matanikau, the U.S. forces strengthened their Lunga defenses. On 14 September Vandegrift moved another battalion, the 3rd Battalion, 2nd Marine Regiment (3/2), from Tulagi to Guadalcanal. On 18 September an Allied naval convoy delivered 4,157 men from the 3rd Provisional Marine Brigade (the 7th Marine Regiment plus a battalion from the 11th Marine Regiment and some additional support units).