Geographically, culturally and historically divided by a central mountain range into a prosperous western sector and isolated eastern sector, Nicaragua is largely overlooked by the Spanish during their conquest of the Americas in the 16th Century. The country becomes a colonial backwater subject to incursions by pirates and foreign interests and to factional conflicts between local cities and landholders.
In the late 17th Century Britain claims sovereignty over the country's Caribbean coast, which effectively remains under British control until the end of the 19th Century.
The declaration of the country's independence in 1838 brings little stability as the United States and Britain vie for influence. The trend of foreign interference in Nicaragua's domestic affairs is further entrenched in 1855 when William Walker, a soldier of fortune from the US, takes over the country. Walker is expelled in 1857 following intervention from all of Nicaragua's neighbours, the British navy and the US marines.
The marines return in 1909 to drive the anti-US dictator José Santos Zelaya from power. They return again in 1912, remaining in the country until August 1925.
Following their withdrawal, the country almost immediately begins to descend into civil war and, in May 1926, the marines return yet again, this time remaining until 1933. On their departure Anastasio Somoza García, the director of the National Guard (the national police force established by the US), begins to lay the groundwork for his ascent to power. He organises the assassination of the resistance leader Augusto César Sandino and the annihilation of Sandino's guerrilla army.
In December 1936 Somoza García is elected president, ushering in a corrupt dynasty that will last for more than four decades and reach a bloody conclusion under the rule of his son Anastasio Somoza Debayle.