Alexander Bathgate was born on 4 August 1845 in Peebles, Peeblesshire, Scotland, the son of Anne Cairns Anderson and her husband, John Bathgate. His father, the local procurator fiscal, had had experience in banking, and had founded a newspaper, the Peeblesshire Monthly Advertiser. Alexander's mother died when he was five or six, and his father remarried.
After schooling in Peebles and Edinburgh and a period at the University of Edinburgh, Alexander, with his parents, brother, two sisters and six half-sisters, migrated to Dunedin, New Zealand, in 1863. John Bathgate was to shape his son's life to a remarkable degree. He became colonial manager of the Bank of Otago, and Alexander worked for several banks in Dunedin, Hamilton's (near Waipiata) and Cromwell. He became articled to G. K. Turton, a lawyer, in 1869, but completed his articles under his father, who had returned to the law in 1870. Alexander was admitted as a barrister and solicitor in 1872, practising until his retirement about 1909. He served as chairman of the Board of Conciliation for the Otago and Southland Industrial District from 1902 to 1908.
Bathgate was a director of several companies, including Kempthorne, Prosser and Company's New Zealand Drug Company, the Trustees, Executors, and Agency Company (both of which he served as chairman), Donaghy's Rope and Twine Company, and the Otago Daily Times and Witness Newspapers Company. His directorship of the last followed many years as a columnist for the company's newspapers as well as for its rivals, such as the Saturday Advertiser and the Evening Star. He sometimes wrote under his own name or used one of several pen-names, including 'He Kete', 'Octogenarian' and 'Mararekareka'. Writing was virtually a second career: Bathgate was a prolific pamphleteer and the author of several books, including novels about colonial life, histories and travel guides.
It was as a conservationist that Bathgate was to become most noted. A Dunedin draper, Thomas Brown, had been instrumental in the establishment of Jubilee Park, a project to commemorate Queen Victoria's 1887 golden jubilee. He was keen to see Dunedin copy the conservation work undertaken in Edinburgh, but having met considerable opposition to the jubilee project, sought someone else to promote his ideas. Bathgate's reputation as a writer and speaker led to Brown's approaching him to act as his publicist. From his childhood in Scotland and through his father's influence Bathgate had acquired a love of nature, and described himself as someone to 'rejoice in green growing things'. His appetite whetted by the Edinburgh books and pamphlets Brown gave him, he became involved in the formation of New Zealand's first conservation organisation, joining the campaign with enthusiasm. After a public meeting failed to rouse the necessary support, he prepared a paper which he delivered to the Otago Institute. The reception he received there led to a second public meeting which, in a blaze of publicity, launched the Dunedin and Suburban Reserves Conservation Society, later known as the Dunedin Amenities Society.
The society, with Bathgate as its secretary, transformed Dunedin's scruffy open spaces into neatly laid-out parks, resplendent with trees and shrubs whose Latin names were painstakingly recorded by Bathgate. It promoted large-scale afforestation, particularly along erosion-prone foreshore areas; ran education programmes for schools; made submissions on the environmental effects of government legislation; and actively encouraged the formation of similar groups in other major cities. Almost single-handed, Bathgate campaigned for the introduction of a national arbor day, his deluge of newspaper articles and pamphlets, complete with draft legislation, bearing fruit in 1892.
Bathgate was equally keen to see Otago prosper economically and was involved in various bodies, such as the Otago Expansion League, concerned with social reform and economic expansion. He worked tirelessly to promote the Otago Central Railway League, seeing rail services as the key to developing the area's orchards. He was also involved in the foundation of the Dunedin Public Art Gallery Society, which he led for over 30 years.
On 24 April 1873 Bathgate had married Fanny Gibson Turton at Dunedin; they had three daughters and a son. Fanny Bathgate died in 1925, five years before her husband's death at Dunedin on 9 September 1930.
Alexander Bathgate's contributions to law, business and journalism may be little known, but Dunedin's public parks – particularly Queen's Gardens and the Octagon – its tree-lined streets, and small pockets of plants and shrubs throughout the city remain as a tribute to his pioneering conservation work.