Largely neglected for years, the so-called "Eastern Route", which connects Ethiopia, via Djibouti, the Bab El-Mandab Strait and Yemen, to Saudi Arabia, began to attract international attention in 2018. That was the year when the Eastern Route overtook the Central Mediterranean as the busiest maritime migration route of the planet with roughly 150,000 crossings, according to the International Organisation for Migration (IOM). The flow continued steadily into 2019 with over 138,000 arrivals from the Horn of Africa to Yemen.

This trend changed dramatically in 2020, when the pandemic shook the Eastern Route. Saudi Arabia and Djibouti tightened border controls, sharply reducing the influx of African migrants into the Arabian Peninsula to only 38,000 people...