There are so many American made cast iron skillets it's hard to claim my "Favorite". From the Ohio Valley to Erie, Pennsylvania, Birmingham, and Florence, Alabama, Sheboygan, Wisconsin, there were hundreds of small towns in the United States that made cast iron cookware, stoves, and kettles. Each had their own style, weight and design. The best thing about all of these companies was the quality of the products they made. I am still using an Erie skillet that was made in 1899!
I will somehow forget a few wonderful American cast iron skillet manufacturers so please forgive me! Erie-Griswold, Wagner Ware, Sidney Hollow Ware Co., Wapak, Favorite Piqua, Lodge, SK, Vollrath, Puritan, Martin Stove and Range, Birmingham Stove and Range. Each manufacturer had a foundry where the skillets were made, and other cooking equipment was also assembled. This was usually in a small town. The foundry employed whole towns! Those days are long gone but our special skillets still keep our meals coming!
It's nice to know there are new companies that have taken on the old tradition of making cast iron cookware! Some include Field Skillets, Finex, Butter Pat, and Smithey Ironware Company.