Charles Gratiot was an American military officer and engineer known for his contributions during the early 19th century. He played a significant role in the construction of military fortifications and infrastructure in the United States, particularly in the Great Lakes region. Gratiot was also involved in the development of the Fort Gratiot military post in Michigan, which was named in his honor. In addition to his military service, Gratiot was recognized for his work in surveying and mapping, which aided in the expansion of the United States. His efforts helped improve transportation and communication routes, contributing to the growth of the nation during a pivotal time in its history.