The sheriff had judicial, electoral, ceremonial and administrative functions and executed High Court Writs.
In 1908, an Order in Council made the Lord-Lieutenant the Sovereign's prime representative in a county and reduced the High Sheriff's precedence.
However the sheriff retained his responsibilities for the preservation of law and order in the county.
The usual procedure for appointing the sheriff from 1660 onwards was that three persons were nominated at the beginning of each year from the county and the Lord Lieutenant then appointed his choice as High Sheriff for the remainder of the year.
The following is an incomplete list: all addresses are in County Westmeath unless stated otherwise.