From my history book, in reference to the Crimean War:
"The war is also remembered for the fashions established at the time. The British general, Lord Raglan, wore an overcoat in which the sleeves went directly to the neck without shoulder seams. Today we call such sleeves 'raglan sleeves'. The leader of the Light Brigade, Lord Cardigan, popularized a sweater that buttoned down the front and could be easily slipped on under a uniform jacket. Sweaters of this type are now known as cardigans. Even the ordinary soldiers in the British ranks introduced a new item. Cold and shivering on the plains of Balaclava, they kept themselves warm by pulling woolen socks over their heads. They cut holes in them for their eyes and mouths. The soldiers called them 'Balaclava helmets'. We call them ski masks."
It almost sounds silly now... we know about cardigan sweaters, so it seems more like Lord Cardigan was named after the sweater, rather than the other way around!