Earl of Howth
Earl of Howth was a title in the Peerage of Ireland. It was created in 1767 for Thomas St Lawrence, 15th Baron Howth. He was made Viscount St Lawrence at the same time, also in the Peerage of Ireland. The St Lawrence family descended from Christopher St Lawrence who was elevated to the Peerage of Ireland as Baron Howth in circa 1425. The third and fourth Barons both served as Lord Chancellor of Ireland.The fourth baron was also a distinguished soldier who fought at the Battle of Knockdoe; his grandson the seventh baron was also a distinguished soldier. The eighth baron, commonly known as " the blind lord " led the opposition to the Government's taxation policy in the 1570s. The ninth baron was an open Roman Catholic who led opposition to the Penal Laws in the early 1600s. The tenth baron was a notable military commander who served with the Earl of Essex and Lord Mountjoy. The fourteenth Baron represented Ratoath in the Irish House of Commons. The third Earl served as Lord-Lieutenant of Dublin. The fourth Earl sat as Member of Parliament for Galway Borough. In 1881 he was created Baron Howth, of Howth in the County of Dublin, in the Peerage of the United Kingdom. However, all the titles became extinct on his death in 1909.
The family seat was Howth Castle, which still belongs to their descendants, the Gaisford St Lawrences. A famous legend, which may have a slight basis in fact, tells that Granuaile, the celebrated Pirate Queen of Galway, arrived uninvited for dinner around 1575 and found the gates locked. Annoyed at the discourtesy, she kidnapped Lord Howth's youthful grandson and held him hostage until the family apologised. By way of amends the family promised that the gates of the castle would always be open at dinner time and an extra place laid for unexpected guests.
Barons Howth (c. 1425) 
- Christopher St Lawrence, 1st Baron Howth (d. 1430)
- Christopher St Lawrence, 2nd Baron Howth (d. 1465)
- Robert St Lawrence, 3rd Baron Howth (d. 1485)
- Nicholas St Lawrence, 4th Baron Howth (d. 1526)
- Christopher St Lawrence, 5th Baron Howth (d. 1542)
- Edward St Lawrence, 6th Baron Howth (1508–1549)
- Richard St Lawrence, 7th Baron Howth (d. 1558)
- Christopher St Lawrence, 8th Baron Howth (d. 1589)
- Nicholas St Lawrence, 9th Baron Howth (1555–1606)
- Christopher St Lawrence, 10th Baron Howth (d. 1619)
- Nicholas St Lawrence, 11th Baron Howth (1597–1643)
- William St Lawrence, 12th Baron Howth (d. 1671)
- Thomas St Lawrence, 13th Baron Howth (1659–1727)
- William St Lawrence, 14th Baron Howth (1688–1748)
- Thomas St Lawrence, 15th Baron Howth (1730–1801) (created Earl of Howth in 1767)
Earls of Howth (1767) 
- Thomas St Lawrence, 1st Earl of Howth (1730–1801)
- William St Lawrence, 2nd Earl of Howth (1752–1822)
- Thomas St Lawrence, 3rd Earl of Howth (1803–1874)
- William Ulick Tristram St Lawrence, 4th Earl of Howth (1827–1909)
- Leigh Rayment's Peerage Pages [self-published source][better source needed]
- Ball, F. Elrington History of Dublin 6 Volumes Alexander Thom and Co Dublin 1902-1920
- Lodge, John and Archdall, Mervyn The Complete Peerage J Murray Dublin 1789
- "St. Lawrence, Robert". Dictionary of National Biography. London: Smith, Elder & Co. 1885–1900.
- "St. Lawrence, Nicholas". Dictionary of National Biography. London: Smith, Elder & Co. 1885–1900.
- "St. Lawrence, Christopher (1568?-1619)". Dictionary of National Biography. London: Smith, Elder & Co. 1885–1900.