The Cook Islands, a sovereign state in free association with New Zealand, uses two official legal tender currencies. The New Zealand Dollar circulates in parallel with the local Cook Islands Dollar; at the same time, the government also authorises many legal tender coins in the Cook Islands Dollar currency for collector's purposes. Many of them are in standard bullion sizes, including one ounce of silver - such as this coin.
This coin is part of the History of the Crusades (Northern Crusades) series and is dedicated to Wendish Crusade.
The Wendish Crusade military campaign started in 1147 and was one of the five major Northern Crusades. It was started because peaceful means by the German archbishops of Bremen and Magdeburg to convert the Wends to Christianity failed. The Wends knew about the plans to invade and thus preemptively invaded Germany but failed. Shortly later in 1147 the march of the Crusaders started. It was the Kingdom of German with the Roman Empire against the Slavic Tribes in now northeast Germany and Poland.
The conquered lands from the Wends were rich in resources which made it easy to find people to join this Holy Crusade. The rewards were high, however the result of the Wendish Crusade was mixed. Lands were conquered, people converted but not to the full extend as planned - similar to the Second Crusade to the Holy Land, which occurred at the same time. | 
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