Kochab, also known as Beta Ursae Minoris, was the naked-eye star that served as the Earth's pole star from 1900 BC to 1100 BC. Due to precession of the equinoxes, the previous holder of the title was Thuban, and the next was the present-day Polaris.
The star is 127 light years from Earth, a K4 III of apparent magnitude 2.2 -- this makes its absolute brightness 190 times that of the Sun, though its surface is cool at 3600 Kelvin. Its mass is estimated to be some 4.4 times that of the Sun. Its name derives from Arabic and means simply "the star".
Kochab, an obscure Arabic name that might simply mean "star," is just barely the second brightest, and appropriately the Beta, star in Ursa Minor, and represents the top front bowl star of the Little Dipper.
Polaris is thus only a temporary pole star that will get better into the next century and then will begin to shift away.
Unlike the Sun, Kochab (which is not particularly unusual among its class), has run out of internal hydrogen fuel, and is an evolving orange giant star that is now running for awhile on the fusion of helium deep in its core.
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