Question

Why did inauguration ceremony takes place in the Amphitheatre form
by union building in Pretoria

Answer 1

because the installation of South Africa's first democratic, non-racial government.

hope it helps you!

Answer 2

$\rm\huge\underline{Answer}$

It was the first democratic, non-racial government taking oath in South Africa. The ceremony was attended by dignitaries from more than 140 countries around the world and thousands of the people of South Africa of all the races to make the day memorable. So, it took place in, the amphiteatre formed by the Union Building in Pretoria