Grenada uses AST (Atlantic Standard Time), UTC-4, year-round. No daylight saving time. At 12 degrees north latitude, the seasonal variation in day length is minimal, making DST impractical.

Grenada is the southernmost of the Windward Islands chain and is known as the Spice Isle: it is one of the world’s largest producers of nutmeg and mace, and also grows significant quantities of cinnamon, cloves, ginger, and turmeric. The nutmeg industry was devastated by Hurricane Ivan in 2004, which destroyed an estimated 90% of the nutmeg crop, and took years to recover.

1983: the US invasion and the reset

Grenada is unusual in that it has a specific date that the entire society reckons from. In October 1983, the United States invaded the island in Operation Urgent Fury, citing the protection of American medical students and concerns about a Cuban-Soviet military presence.

The invasion came days after a coup in which Prime Minister Maurice Bishop, a popular socialist leader, was executed by hardline faction members within his own New Jewel Movement government. The US moved quickly.

The operation was controversial internationally. The United Nations General Assembly voted 108 to 9 that it was a “flagrant violation of international law.” Britain, a Commonwealth partner, was not consulted beforehand, which strained relations between Margaret Thatcher and Ronald Reagan.

The invasion lasted days. Grenada’s subsequent history moved toward multi-party democracy.

None of this changed the timezone. Grenada has been UTC-4 throughout.

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