General Casualty Insurance

General Casualty Insurance was a super-regional property and casualty insurance provider headquartered in Sun Prairie, Wisconsin as of 2006.

Winterthur U.S. Holdings, which operated as Winterthur North America, and was also based in Sun Prairie, Wisconsin operated General Casualty Insurance, as well as Bellevue, Washington-based Unigard Insurance.

Winterthur North America was a subsidiary of Switzerland-based Winterthur Swiss Insurance Group, which was part of banking giant Credit Suisse Group.

In January, 2007, QBE Insurance Group, Sydney, Australia, agreed to buy Winterthur U.S. Holdings, the Sun Prairie-based parent company of General Casualty and Unigard Insurance Group of Bellevue, Washington, for $1.16 billion.