When the Democratic National Committee announced that Denver had been selected to host the 2008 Democratic convention, it appeared for a while that those plans could be derailed because of Denver's lack of unionized hotels. It seemed that many of those who welcomed the convention thought that organized labor's objections were bothersome at best and ridiculous at worst.

But beneath the surface of the dispute is a history of labor-management relations in Colorado that at one time was shocking in its intensity and manifestly bloody. It reached a nadir in 1913-1914 when, for 15 months, Colorado was the epicenter of a union-management war that cost 75 people their lives. Twenty-one of those, mostly women and children, were killed in a town between Walsenburg and Trinidad called Ludlow.

The events surrounding what came to be known as the Ludlow Massacre were less about "the romantic notion of the resilience of the union men and women in the face of oppression," and more about class distinctions played out against the incidental backdrop of an ugly strike, according to journalist Scott Martelle in an impressive new book about the conflict.