During the time of the Penal Laws, George went to Spain where he was admitted to the Royal Court. From the 1760s until about 1790, George made his fortune in the wine and brandy trade, running his business from Alicante. When the Penal Laws were relaxed at the end of the 18th century, he returned to Mayo with a fortune of £200,000 and in 1783, bought over 12,000 acres (49 km2) of land at Muckloon, Ballycally and Killeen from Farragh Mc Donnell, and commissioned the building of the grand residence of Moore Hall.
George’s son, John Moore (1767 – 1799), was educated in France and became a lawyer. With the rebellion of 1798, he returned to Mayo. General Humbert appointed him President of the Connacht Republic in Castlebar. Thus, John Moore was the first President of an Irish republic, albeit for a very brief interval. He was captured by the English Lord Cornwallis and, although initially sentenced to death, his sentence was later commuted to deportation. He died in the Royal Oak tavern in Waterford on 6 December, 1799. His body was exhumed from Ballygunnermore Cemetery in Waterford in 1962 and brought to Castlebar, where he was buried in the Mall with full military honours.
George Henry Moore (1810 – 1870), was educated in the Catholic faith in England and later at Cambridge University. His main interest was in horses and horse-racing. His brother, Arthur Augustus, was killed after a fall from the horse Mickey Free during the 1845Aintree Grand National. At the height of the Great Irish Famine in 1846, he entered a horse called Coranna for the Chester Gold Cup and netted £17,000 from bets laid on the horse. During the Famine he imported thousands of tons of grain to feed his tenants, and gave each of his Mayo tenants a cow from his winnings. It is still remembered on the Moore estate that nobody was evicted from their home for non-payment of rent during hard times, and that nobody died there during the Famine. George Henry is buried in the family vault at Kiltoom on the Moore Hall estate.
George Agustus Moore (1852 – 1933), was a distinguished writer of the Irish Literary Revival period. Many famous writers of the time, including Lady Gregory, Maria Edgeworth, George Osborne, and W. B. Yeats were regular visitors to Moore Hall. George was an agnostic, and anti-Catholic. His ashes are buried on Castle Island on Lough Carra in view of the big house on the hill.
Maurice George Moore (1854 – 1939), Senator Colonel Maurice Moore was the statesman of the family. He served with the Connaught Rangers in the Boer War and became concerned with human rights in South Africa. He also worked to relieve Irish prisoners held in English jails, and for the retention of UCG when it came under threat. He was also involved with the co-operative movement in Ireland, founded by Horace Plunkett.