The Crown In The Commonwealth Realms

The evolution of the Commonwealth realms has resulted in the Crown having both a shared and a separate character, with the one individual being equally monarch of each state and acting as such in right of a particular realm as a distinct legal person guided only by the advice of the cabinet of that jurisdiction.....

This means that in different contexts the term Crown may refer to the extra-national institution associating all 16 countries, or to the Crown in each realm considered separately.

However, though the monarchy is therefore no longer an exclusively British institution,having become "domesticated" in each of the realms,it may in the media and legal fields often still be elaborated as the British Crown for reasons historical, of convenience, or political, regardless of the different, specific, and official national titles and terms used when addressing the Queen of the citizenry in each jurisdiction. 

For example, in Barbados the Queen is titled as Elizabeth II, Queen of Barbados, or simply the Queen of Barbados, with her full title making mention of her position as queen of the other Commonwealth realms.

From a cultural standpoint, the sovereign's name and image and other royal symbols unique to each nation are visible in the emblems and insignia of governmental institutions and militia. 

The Queen's effigy, for example, appears on coins and banknotes in some countries, and an oath of allegiance to the Queen is usually required from politicians, judges, military members and new citizens. By 1959, it was being asserted by Buckingham Palace officials that the Queen was "equally at home in all her realms."