迦勒底（一译加尔底亚，阿拉伯语：كلدان‎‎，Kāldān），是一个古代地区的名称，属巴比伦尼亚南部，即现今伊拉克南部及科威特。公元前625年至前539年期间开始有部落进入该区居住，这些部落的住民就被称之为迦勒底人、加尔底亚人或新巴比伦人。

在《旧约圣经》中，迦勒底是新巴比伦的同义词。大约在公元前625年，迦勒底人夺得巴比伦尼亚的王位，创建了迦勒底王朝，亦即新巴比伦王国。尼布甲尼撒二世在位时，帝国版图大为扩张，势力达至顶峰，征服犹大王国，并攻占了耶路撒冷。

Chaldea (/kælˈdiːə/), from Ancient Greek: Χαλδαία, Chaldaia; Akkadian:māt Kaldu/Kašdu; Hebrew:כשדים‎, Kaśdim; Aramaic:ܟܠܕܘ‎, Kaldo, also spelled Chaldaea, was a small Semitic nation that emerged between the late 10th and early 9th century BC, surviving until the mid 6th century BC, after which it disappeared as the Chaldean tribes were absorbed into the native population of Babylonia. It was located in the marshy land of the far southeastern corner of Mesopotamia, and briefly came to rule Babylon.