An alliance is an agreement between two or more parties, made in order to advance common goals and to secure common interests. The Anglo-Portuguese Alliance between England (succeeded by the United Kingdom) and Portugal is the oldest alliance in the world which is still in force. It was signed in 1373.
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Horde, a term of Turkic origin meaning a clan of nomads (ultimately from the Turkic ordu, orda meaning "encampment" , cf. Tatar: Urda; Mongolian: Ордын; Turkish: 'Ordu'; cf. the related term yurt). 'Ordu' is also the word for 'Army' in Persian of Afghanistan.