|2 January||U. S. Army troops land at Saidor, beginning drive up New Guinea coast.|
|30 January-23 February||U. S. Marines and Army troops seize Marshall Islands.|
|16-17 February||Task Force 58 strikes Truk, revealing weakness of that base. Decision to by-pass comes soon after.|
|22-23 February||Task Force 58 strikes Southern Marianas.|
|29 February||U. S. Army troops land at Los Negros in the Admiralties.|
|6 March||1st Marine Division lands near Talasea on New Britain.|
|12 March||Joint Chiefs of Staff direct seizure of Southern Marianas, target date 15 June.|
|20 March||4th Marines (Reinforced) seize Emirau.|
|20 March||Admiral Nimitz issues FORAGER Joint Staff Study setting forth the purpose of the Marianas Operation.|
|23 March||Admiral Nimitz issues operation order for Marianas; Admirals Spruance and Turner follow suit.|
|30 March-1 April||Task Force 58 strikes Western Carolines.|
|22 April||U. S. Army troops land at Hollandia and Aitape.|
|26 April||Expeditionary Troops operation order states mission ". . . to capture, occupy and defend Saipan, Tinian and Guam. . . ."|
|17-19 May||Northern Troops and Landing Force maneuvers and rehearses at Maui and Kahoolawe, Hawaiian Islands.|
|21 May||Six LVT's, embarking assault elements of the 2d and 4th Divisions, burn at Pearl Harbor.|
|25 May||LVT's, carrying assault elements of the 2d and 4th Marine Divisions, LVT's and artillery, depart Pearl Harbor.|
|29-30 May||Portions of the Northern Troops and Landing Force not embarked in LVT's, depart Pearl Harbor.|
|6 June||D-Day in Normandy.|
|11 June||Northern Attack Force departs Eniwetok for Saipan.|
|11 June||Task Force 58 begins bombardment of Tinian and Saipan.|
|14 June||Fire support ships of the Northern and Southern Attack Forces commence bombardment of Saipan and Tinian.|
|15 June||2d and 4th Marine Divisions land at Saipan.|
|16 June||27th Infantry Division begins landing at Saipan.
Guam bombardment by surface ships commences.
|19-20 June||Battle of the Philippine Sea. Japanese Navy suffers decisive defeat.|
|20 June||Battery B, 531st Field Artillery Battalion, XXIV Corps Artillery, commences fires on Tinian from Saipan positions.|
|21 June||Aslito Airfield on Saipan becomes operational for fighter aircraft.|
|24 June||Entire 531st Field Artillery Battalion commences firing on Tinian from Saipan positions.|
|26 June||Admiral Turner issues new plan for intensification of Tinian bombardment.|
|6-7 July||Japanese launch savage all-out attack along Tanapag Plain, Saipan.|
|9 July||4th Marine Division reaches Marpi Point; Saipan declared secured; mop-up begins.|
|10 July||2d and 4th Marine Divisions get ready for Tinian operation.|
|10-11 July||Amphibious Reconnaissance Battalion, V Amphibious Corps, and Underwater Demolition Team 5 reconnoiter Tinian landing beaches.|
|12 July||Major General Harry Schmidt assumes command of Northern Troops and Landing Force, relieving Lieutenant General Holland M. Smith; Major General Clifton B. Cates assumes command of the 4th Marine Division.
Capture and Occupation Phase for Saipan ends; Defense and Development Phase begins under command of Major General Sanderford Jarman, USA.
|13 July||Northern Troops and Landing Force issues Tinian Operation Order.|
|15 July||Rear Admiral Harry W. Hill assumes command of the Northern Attack Force, relieving Vice Admiral Richmond K. Turner.|
|18 July||Japanese Premier Hideki Tojo and Cabinet resigns.|
|20 July||First troops for Tinian invasion embark aboard ships at Saipan.|
|21 July||Southern Troops and Landing Force lands on Guam.|
|24 July||4th Marine Division lands on Tinian.|
|24-25 July||Japanese launch powerful night counterattacks against 4th Marine Division beachhead, suffer decisive defeat.|
|25 July||2d Marine Division lands on Tinian.|
|27 July||Ushi Point Air field, Tinian, becomes operational.|
|30 July||Tinian Town captured.|
|31 July||At 0200, Japanese counterattack strikes 1st and 2d Battalions, 8th Marines, on Tinian.|
|1 August||All organized resistance ceases on Tinian; island declared secured.|
|3 August||At 1500, American flag is officially raised over Tinian.|
|9 August||Aslito Airfield, Saipan, becomes operational for Liberator bombers (B-24's).|
|10 August||Organized resistance ends on Guam; island declared secured.|
|Northern Troops and Landing Force as a task force designation is dissolved; staff resumes duties as V Amphibious Corps Staff.|
|10 August||Capture and Occupation Phase for Tinian ends; Defense and Development Phase begins under island commander, Major General James L. Underwood, USMC.|
|12 August||Commander Forward Area (Vice Admiral John H. Hoover) relieves Commander Joint Expeditionary Force (Vice Admiral Richmond K. Turner) of responsibility for Defense and Development of Saipan and Tinian.|
|14 August||Major General Harry Schmidt relieves Lieutenant General Holland M. Smith as Commanding General, Expeditionary Troops.
Major General Allen H. Turnage relieves Major General Roy S. Geiger as Commanding General, Southern Troops and Landing Force.
|15 August||Commander Forward Area (Vice Admiral John H. Hoover) relieves Admiral Turner of responsibility for the Defense and Development of Guam. TF 51 (Joint Expeditionary Force) is dissolved.
The Capture and Occupation Phase of Guam ends. Major General Henry L. Larsen, USMC., takes over command of the Guam Garrison Force.
|15 September||1st Marine Division lands at Peleliu; U. S. Army troops seize Morotai.|
|17 September||U. S. Army troops land on Angaur.|
|23 September||U. S. Army troops seize Ulithi as advanced naval base.|
|15 October||Aslito Airfield, Saipan, becomes operational for B-29's.|
|20 October||U. S. Army troops land at Leyte and open Philippines Campaign.|
|25 October||8th Marines (less 1st Battalion) leaves Tinian and moves to Saipan.|
|24 November||Saipan-based B-29's raid Tokyo.|
|30 December||B-29's land at Tinian.|
|1 January||1st Battalion, 8th Marines, after five months' garrison duty, leaves Tinian and moves to Saipan.|
|4 February||Tinian-based B-29's raid Kobe area, Japan.|
|6 August||Atomic bomb, carried by Tinian-based B-29, is dropped on Hiroshima.|
|9 August||Second atomic bomb carried from Tinian dropped on Nagasaki.|
|10 August||Japan sues for peace.|
1.Entries relating specifically to the Tinian operation are shown in italics.