Unlike the colonies of Hong Kong and Macau, where the United Kingdom and Portugal enjoyed full sovereignty in perpetuity, the foreign concessions in China remained under Chinese sovereignty. In 1854, the three countries created the Shanghai Municipal Council to serve all their interests, but, in 1862, the French concession dropped out of the arrangement. The following year the British and American settlements formally united to create the Shanghai International Settlement. As more foreign powers entered into treaty relations with China, their nationals also became part of the administration of the settlement, but it always remained a predominantly British affair until the growth of Japan's involvement in the late 1930s. The international character of the Settlement was reflected in the flag and seal of the Municipal Council, which featured the flags of several countries.