Among his ancestors was a brother of John Christopher Hartwick, a Lutheran minister who emigrated to the United States from Germany in the early decades of the 18th century.

A year later, in September 1889, Hartwick left Michigan to enroll at the United States Military Academy at West Point.

The country is covered with dense undergrowth and great caution had to be exercised to avoid being ambushed by the enemy.

[4]An interesting account of the Battle of San Juan Hill appears in Hartwick's biography in which he is quoted as saying, among things, "The above claim of Colonel Roosevelt is not true":[5] The claim had to do with exactly when and how and why Teddy Roosevelt "led" the charge up San Juan Hill.

Hartwick left Cuba to return to Grayling and on October 19, 1898, married Karen Bessie Michelson.

[6] Following the United States' entry into World War I Hartwick volunteered for service and was commissioned a major in the 20th Engineers.

[8] The Edward E. Hartwick Memorial Building museum within the park is listed on the National Register of Historic Places.