Under Augustus and after the conquest of Egypt there were increasing demands from the Roman economy to extend the trade lanes to India. The Arabian control of all sea routes to India was an obstacle. One of the first naval operations under "princeps" Augustus was therefore the preparation for a campaign on the Arabian Peninsula. Aelius Gallus, the prefect of Egypt ordered the construction of 130 transports and subsequently carried 10,000 soldiers to Arabia. But the following march through the desert towards Yemen failed and the plans for control of the Arabian peninsula had to be abandoned.