Gold has been a major force in the government and politics of Hauraki–Coromandel. In the historical mining era, several levels of settler government contested the control of gold revenues. Māori had little political influence after 1870, as local members of Parliament voiced miners’ concerns.
Localism has been another influence: localities chose to break away from parent counties, to concentrate resources and expertise on their particular needs. Local government amalgamations in 1975 and 1989 reversed this process.
In a poll in 1908 Ōhinemuri voted to go dry – to prohibit the sale of liquor within the district, a ban which lasted until 1926. Miners from Waihī would catch the train to the Pioneer hotel at Hikutaiā, just beyond the county boundary, and return, drunk and disorderly, hours later.
In 1975 Thames-Coromandel district council replaced Thames and Coromandel counties and Thames borough.
In 1989 Hauraki district council replaced Hauraki Plains and most of Ōhinemuri counties and Paeroa and Waihī boroughs.
Thames and Coromandel achieved early prominence in national politics because of strong local representation and the importance of gold mining to the national economy. George Grey, formerly the governor, won the Thames seat in 1876 and served as premier from 1877 to 1879.
Alfred Cadman, a sawmiller and former member for Coromandel, was elected to the Thames seat in 1890. He held important portfolios in the Liberal governments of the 1890s. Liberal domination of the Thames electorate was based on miners’ support.
At the 1935 general election the Ōhinemuri electorate (incorporating Ōhinemuri , Thames and Coromandel) joined the landslide to the Labour Party. By the 1940s, however, the region also included a substantial small-town and farming vote. The National Party won the Thames electorate in 1946. The Social Credit party polled well among disgruntled small farmers in the 1970s, but National’s hold was never seriously threatened.
In the 1999 general election Jeanette Fitzsimons won the Coromandel seat for the Green Party, ending a 53-year-long National electoral hold on it. In 2002 Sandra Goudie won back Coromandel for National. She was succeeded by Scott Simpson in 2011.
Until 2022 Hauraki–Coromandel was served by Waikato district health board and, before that, Waikato hospital board. Thames hospital serves the region, and has a dedicated birthing unit.
Thames High School, established in 1880, is one of the oldest secondary schools in the upper North Island. In 2010 other secondary schools included Paeroa College, Hauraki Plains College (formerly Ngatea District High School) and Waihi College. There are area schools (combined primary and secondary) on the peninsula at Coromandel, Whitianga (Mercury Bay) and Whangamatā.