Context: Independence was unilaterally declared on 24 September 1973. Recognition became universal following the 25 April 1974 socialist-inspired military coup in Portugal, which overthrew Lisbon's Estado Novo regime.

Question: When was independence declared?
Answer: 24 September 1973

Question: What date was independence considered universal? 
Answer: 25 April 1974

Question: What event caused the recognition to be universal?
Answer: socialist-inspired military coup

Question: Where did a coup take place?
Answer: Portugal

Question: Who was overthrown in the coup?
Answer: Lisbon's Estado Novo regime