  A spectroscopic orbit has been recently found by R. Griffin for the long
known barium star 56 Peg, which is also a strong X-ray source. This
short-period, low mass-function orbit raises several questions regarding the
history of the system. In the present paper, we show that it is not easy to
find an evolutionary history for 56 Peg which is consistent with the current
component's masses, unless one assumes that the giant is a relatively fast
rotator (a few times 10 km/s). The hypothesis of fast rotation allows us to
explain some other peculiarities of this object as well.
