Explanation:
HUGH CAPET:
He was the successor of Louis V of France. He was the founder and the first king from the house of Capet (Capetian Dynasty).
He ruled France from 3rd July, 987 to 24th October, 996.
His greatest achievement was - the house (of Capet) he founded ruled France continuously for seven generations.
KING FERDINAND AND QUEEN ISABELLA:
They were cousins, but later became married. Their greatest achievement was their help in unifying Spain, turning it into the great nation that it is.
They also helped in funding the voyage of exploration across the Atlantic Ocean of Christopher Columbus.
They reigned from 11th December, 1474 to 26th November, 1504.
JOAN OF ARC:
Her greatest achievement was - at the age of eighteen, she led the French army to war and was victorious over the English at Orleans.
She was canonized as a Roman Catholic saint on 16th May, 1920, over five hundred years after she was burned at the stake as a heretic by the English and their French allies.
