(g hard). To run the gantlet. To be hounded on all sides. Corruption of gantlope, the passage between two files of soldiers. (German, ganglaufen or gassenlaufen.) The reference is to a punishment common among sailors. If a companion had disgraced himself, the crew, provided with gauntlets or ropes' ends, were drawn up in two rows facing each other, and the delinquent had to run between them, while every man dealt him, in passing, as severe a chastisement as he could.
The custom exists among the North American Indians. (See Fenimore Cooper and Mayne Reid.)
“It is not for Spain, reduced as she is to the lowest degree of social inanition, to throw the gauntlet to the right and left.” —The Times.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Gauntlet from Infoplease: