Question: Where does a moment of silence come from?
Disambiguated questions and answers: question: What country is the first recorded moment of silence come from?
Who is the first recorded moment of silence come for?
Who participated in the first recorded moment of silence?
answer: Portugal
José Maria da Silva Paranhos Júnior
José Paranhos, Baron of Rio Branco
Portuguese Senate
Natural Questions answer: Quakers (from the Wikipedia article "Moment of silence")