<P> As was the case throughout the British Empire, the Red and Blue Ensigns were the official flags for merchant and government vessels at sea, and the British Admiralty authorised them to be defaced in the fly with the shield from the South African coat of arms . These ensigns were not intended to be used as the Union's national flag, although they were used by some people as such . Although these ensigns were primarily intended for maritime use, they were also flown on land . </P> <Ul> <Li> <P> The South Africa Red Ensign was South Africa's de facto national flag between 1910 and 1928 and was flown at times from Government buildings . </P> </Li> <Li> <P> The design of the Red Ensign was modified slightly in 1912 when the shield was placed on a white disc so as to make it more distinguishable . The Red Ensign continued to be used as the flag of the South African merchant marine until 1951 . </P> </Li> <Li> <P> The Blue Ensign was flown over the Union's offices abroad between 1910 and 1928 . </P> </Li> <Li> <P> The Blue Ensign from 1912 to 1928 . </P> </Li> </Ul> <Li> <P> The South Africa Red Ensign was South Africa's de facto national flag between 1910 and 1928 and was flown at times from Government buildings . </P> </Li> <P> The South Africa Red Ensign was South Africa's de facto national flag between 1910 and 1928 and was flown at times from Government buildings . </P>

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