The 150th Anniversary of the Independence of the Argentine Republic was on July 9, 1966. To strengthen friendly relations between the Argentine Republic and the Republic of China, a commemorative postage stamp was issued. The territory of present-day Argentina had been a part of the Spanish colonial empire for nearly three hundred years, since 1526. It became an independent nation known as the Argentine Republic on July 9, 1816 after a lengthy and hard struggle which was started in 1810 by Argentine patriots.