The 1100s BC is a decade which lasted from 1109 BC to 1100 BC.

• 1104 BC—Foundation of Cadiz, Spain.^[1][2]
• 1100 BC—Tiglath-Pileser I of Assyria conquers the Hittites.
• c. 1100 BC—Maya Calendar counts time from this point.
• c. 1100 BC—The Dorians invade Ancient Greece.
• c. 1100 BC—Mycenaean era ends with the destruction of that civilization. The collapse of Mycenaean dominance starts.
• c. 1100 BC—Late Minoan culture ends.
• c. 1100 BC—Greek Dark Ages begin.
• c. 1100 BC—Beginning of the proto-Villanovan culture in northern Italy.
• c. 1100 BC—The New Kingdom in Egypt comes to an end.
• c. 1100 BC—The Shang dynasty ends in China.
• c. 1100 BC—Kurukshetra War begins in Later Vedic period in Kuru Kingdom.

• c. 1102 BC—Samuel is born.
• c. 1100 BC—Zarathustra is born.

• Alphabet, developed by Phoenicians.
• MUL.APIN, developed by Assyrians: an ancient catalog of constellations.