Why was the Kingdom of Axum an important region on the Silk Road?

The Kingdom of Axum was an important region in the Silk Road, because they had their own currency, which facilitated trade in the Silk Road trade and although it was sovereign, it sometimes entered the politics of the Arabian Peninsula, so it is safe to say that it was known and had good relations with it's neighbors and the people coming in and the people going out. Slowly afterwards, they started expanding their rule over the Arabian Peninsula.