The Actions along the Matanikau—sometimes referred to as the Second and Third Battles of the Matanikau—were two separate but related Cause_to_be_included engagements Hostile_encounter , which took place Process_start in the months of September and October 1942 , among a series of engagements between the United States and Imperial Japanese naval and ground forces Causation around the Matanikau River on Guadalcanal ( island in the southwestern Pacific , northeast of Australia ) during the Guadalcanal Campaign .

These particular engagements—the first taking place Process_start between 23 and 27 September , and the second between 6 and 9 October—were two of the largest and most significant of the Matanikau actions .

The Matanikau River area included Cause_to_be_included a peninsula called Request Point Cruz , the village of Kokumbona , and a series of ridges and ravines stretching inland from the coast .

In the first action , elements of three U.S. Marine battalions under the command Control of U.S. Marine Major General Alexander Vandegrift attacked Attack Japanese troop concentrations at several points around the Matanikau River .

The Marine attacks Attack were intended to `` mop-up '' Japanese stragglers retreating Escaping towards the Matanikau from the recent Battle of Edson 's Ridge , to disrupt Destroying Japanese attempts to use the Matanikau area as a base for attacks Attack on the Marine Lunga defenses , and to destroy Destroying any Japanese forces Causation in the area .

The Marine attacks Attack were intended to `` mop-up '' Japanese stragglers retreating Escaping towards the Matanikau from the recent Battle of Edson 's Ridge , to disrupt Destroying Japanese attempts to use the Matanikau area as a base for attacks Attack on the Marine Lunga defenses , and to destroy Destroying any Japanese forces Causation in the area .

In the second action two weeks later , a larger force of U.S. Marines successfully crossed Motion_directional the Matanikau River , attacked Attack Japanese forces Causation under the command Control of newly arrived generals Masao Maruyama and Yumio Nasu , and inflicted heavy casualties Damaging on a Japanese infantry regiment .

The second action forced Motion the Japanese to retreat Escaping from their positions east of the Matanikau and hindered Preventing_or_letting Japanese preparations for their planned Arranging major offensive on the U.S. Lunga defenses set for later in October 1942 that resulted in Causation the Battle for Henderson Field .