In the late 19th century, the Hamilton Watch Company was established in the state of Pennsylvania, USA. The pocket watches manufactured by the company were initially used as timing devices for the nation's railroads, trusted for their accuracy and reliability. The reputation of Hamilton timepieces led to the company being appointed as supplier for the US armed forces; with this appointment, the watchmakers shifted from pocket watch to wristwatch production. After the Second World War, the Hamilton Watch Company returned its focus to its commercial market and to technological development. In 1957, the 'Ventura' was released as the world's first electric watch - later worn by Elvis Presly in the iconic film, Blue Hawaii. The next innovation from Hamilton was the 'Pan Europ', marketed as one of the first automatic chronographs. Since becoming part of the Swatch Group, Hamilton watches have appeared in numerous blockbuster movies, including cult-classic Die Hard and recent hit Interstellar.