Until World War II the Marshall Islands followed much the same historical path as the other island nations in Micronesia; first there were people who spent a couple thousand years developing their own clan-based culture, then there was Spanish exploration, then German colonization resulting in the islands becoming part of German New Guinea, then, in 1914, absorption into the Japanese empire. The Japanese settled the Marshall Islands heavily and replaced local paramount chiefs, who had ruled the Marshall Islands for centuries, with Japanese-appointed leaders. They redistributed land and tried, with marginal success, to change the Marshallese system of matrilineal descent to one of patrilineal descent. By the time World War II began the Japanese had used Korean forced labor to develop a naval base on the Marshallese Kwajalein Atoll and had relocated most of the population from Kwajelein to other atolls. During World War II the United States bombed Kawjalein extensively and then invaded in 1944. The battles were harsh and many Japanese, Koreans, Marshallese and Americans perished there. After taking Kawjalein Atoll the U.S. used it as a staging base for more Pacific campaigns.
After the War the United States developed the Marshall Islands as a Trust Territory and at first treated the Marshallese as captured Japanese subjects, strongly discouraging any pro-Japanese sentiment. They also not only kept their military presence in the islands, but transformed some of their facilities into command centers for “the Pacific Proving Grounds,” a series of sites in the Marshall Islands used to test nuclear weapons. Over the next two decades the U.S. detonated over a hundred nuclear weapons there. (See this photo of the “Baker” explosion at Bikini Atoll in 1946.) One of the explosions in particular, codenamed Castle Bravo, was much larger than the U.S. scientists expected and severely contaminated several Marshallese atolls, including Bikini Atoll. Since 1956 the United States has paid at least $759 million to Marshall Islanders to compensate them for their exposure to radiation.
In 1979 the Marshall Islands became independent since then the nation has signed a Compact of Free Association with the United States. The compact assures the Marshall Islands of U.S. military defense while also allowing the U.S. to maintain a missile testing facility on Kwajalein Atoll. The Marshallese elect members of the parliament, the Nitijela, with representatives coming from islands and atolls throughout the island group. Legislation happens in the Nitijela. The upper house of the Marshallese parliament, the Council of Iroij, is an advisory group composed of twelve chiefs. Four of the five Marshallese presidents since 1979 have been paramount chiefs.
The website of the Marshallese Embassy in the U.S. gives us a decent timeline of Marshallese history and also an overview of Marshallese culture | Land is at a premium in the Marshall Islands and Marshallese land ownership customs are complex. This handy introduction to Marshallese Land Ownership explains the three primary classes of land ownership, which are intertwined with the three social classes in the Marshalls: iroij (chief); alap (owner or elder); and (c) rijerbal (worker or commoner)