Which landlocked Southern African country, heavily reliant on South African ports, is known for its traditional Swazi culture and boasts a king as its head of state?

1. Its economy is closely tied to South Africa's and its currency is pegged to the South African Rand.
2. It's one of the smallest countries in Africa.
3. The annual Umhlanga Reed Dance is a significant cultural event.
4. It changed its name in 2018.