Van Ierland was born in Tilburg, located in the Dutch province of North Brabant, on 5 May 1914. He was married in 1944, and fathered six children. He studied physics in Delft, then gained an interest in psychology and chose to pursue the field. He worked as a graphic designer.
Since 2003, he has been in a LAT relationship with his partner Anneke. They had known each other for years, and after his wife’s death, a cousin of his reintroduced the two. He regularly walks around his garden to the apple tree and his bench.
Following the death of Eelke Bakker on 3 May 2020, Van Ierland, then two days shy of 106, became the oldest native Dutchman and the second-oldest man in the country, after John Huang.
Van Ierland became the oldest living person born in the Netherlands upon the death of Marina van der Es-Siewers on 11 March 2024; in addition, he also became the second-oldest resident of the country after Huang. In May of that year, he became the first native Dutch male to attain supercentenarian status since Cornelis Geurtz in 2012.
His age was verified by Marco Wikkerink, and validated by the ESO on 14 May 2024.
Over twee maanden wordt hij 110 jaar oud, maar Jan van Ierland hoopt het nog wat langer vol te houden Noordhollands Dagblad, 10 March 2024