Subseries I: General Subject Files, 1848-1966, undated

Files in this subseries largely concern real estate transactions, loans and financial assistance to family members, friends, and business associates, and investments in railroads, utilities, mining, banking, and manufacturing. Other topics of interest include Frick's private railroad car "Westmoreland," the family's box at the Metropolitan Opera; social events hosted by the Frick family, and membership in a range of clubs, societies, and other organizations. These papers also occasionally contain information regarding philanthropic endeavors, art purchases, and the lease of various properties, including the Vanderbilt mansion at 640 Fifth Avenue in New York, the Robert S. Bradley house in Prides Crossing, Mass., a vacation cottage in Palm Beach, Fla., apartments at Louis Sherry's in New York, and charter of the yacht Shemara. An alphabetical index of topics and their corresponding envelope numbers is filed in the beginning of the subseries. Note that some gaps exist among the sequence of envelope numbers, and that some envelopes are empty, indicating that their contents may have been removed and stored elsewhere by Frick's office staff. The location of materials transferred out of these files is often unclear.

Folders are arranged by envelope number.