The Boxer breed was developed during the 19th century in Germany. They are said to be a mix of mastiffs, bulldogs, Great Danes, and possibly terriers. Boxers were imported to America after World War I, where they became one of the most popular breeds in a short time. Boxers have been used as police, seeing-eye, and guard dogs. They also make loyal companions and are great around children. They range from 21 to 25 inches high and weigh 50 to 80 pounds. Humphery Bogart and Lauren Bacall were two famous Boxer lovers.