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In 1940 the German army entered the Netherlands, beginning an occupation that lasted five years. Members of the Dutch royal family(荷兰皇室) were forced to go to the United Kingdom to avoid being caught. However, the threat of German bombing attacks meant that England was not completely safe. For this reason Princess Juliana and her daughters, Princesses Beatrix and Irene, moved to Canada and settled in Ottawa. In January 1943 Juliana gave birth to a third daughter, Princess Margriet Francisca. The Government of Canada temporarily declared her place of birth as outside of Canadian land, meaning Margriet could hold Dutch citizenship and therefore still be qualified for the Dutch throne.
In 1945, the Dutch royal family returned home. Shortly after her return, Princess Juliana presented 100,000 tulip bulbs to Canada in appreciation of the important role played by Canadian troops in liberating the Netherlands and for providing her family with a safe place during the war. The following year she sent 20,500 tulip bulbs. Juliana continued to send thousands of bulbs as a yearly gift, a tradition that continued after she became queen in 1948. The gift of tulips is an ongoing tradition, and each year the people of the Netherlands and the Dutch royal family each send 10,000 bulbs to Canada in recognition of the close ties between the two countries. The gift of bulbs and the tulip flowers attracted interest and visitors in Ottawa. In 1952 Karsh, an Armenian-born photographer, suggested the idea of a tulip festival to the Ottawa Board of Trade. The first Canadian Tulip Festival took place in 1953. The first festival proved popular, and it became a yearly event. To mark the festival's 50th anniversary in 2002, Canada Post issued a series of commemorative stamps(纪念邮票) and plates featuring the flowers and Princess Margriet returned to visit Ottawa. In the following years the festival began to focus more on international friendship and the festival's historical origins. Now it is one of the world's largest tulip shows.
