A log marking hammer was an essential tool in the logging industry, particularly during the 19th and early 20th centuries. It was used to stamp ownership marks onto logs before they were transported down rivers to sawmills. These hammers had a unique, custom-made metal stamp on one end, often featuring letters, numbers, or symbols that identified the logging company or owner.

During the height of river-driven logging, thousands of logs from multiple companies would be floated together. To prevent disputes over ownership, each log was marked at the time of felling or before reaching sorting stations.

As railroads and trucks gradually replaced river drives, the need for log marking hammers declined. However, they remain significant artifacts of logging history, symbolizing the era when rivers served as highways for the timber industry.