The key piece of information about Picton is that he was born in Carmarthen, so it seems likely the street name, unique in the world, is due to a typo and should really be Carmarthen St.
Lansdowne's streets have an interesting history because they reflect a deliberate naming policy unlike most of Masterton. Until 1921 the suburb of Lansdowne was part of the Masterton County, rather than being part of the town, and in 1904 the county formulated a policy for naming the streets in what was a rapidly expanding residential area.
The area bounded by the roads to Opaki and Castlepoint was part of the large landholdings of Wairarapa's first MP, John Valentine Smith. Smith kept a house on Lansdowne as his town house, although he also had a large sheep station at Mataikona, and shifted to Nelson while his sons were educated at Nelson College. When it came to naming his town estate he chose the name of the area of Australia where he wife, Mary Emmeline Wild, came from, Lansdowne, near Sydney.
The Masterton County Council resolution of July 1904 decreed that streets should be named after "local residents, noted commanders, native trees, numbers and noted public entertainers". Fortunately, the last of the denominators has never been used, and we have been spared "One Direction Way" and "Spice Girls St", but the others have all been used. Lett St, Bolton's Rd and Cooper St have all been named after local developers, while many streets recall British military commanders - Roberts, French, Raglan, and Gordon. Others commemorate native trees - Rimu, Totara, Niaku and, more recently, Tarata - while the streets from Opaki Rd have been named in the American manner - First, Second and so on.
One street was renamed in the 1940s. The Terrace was named in the usual New Zealand pragmatic manner - it was a road that ran along the terrace that overlooked Masterton. It was the site of William and Emma Adams' house, Mount Pleasant. William Adams was the first white person to live on the site of Masterton is his job as shepherd for Richard Collins at Te Ore Ore, while Emma was the daughter of Michael Dixon (of Michael St fame). Their property, in particular the portion on the northern side of the Waipoua River, was known as "Adamsville", but when as street was constructed through it in the 1900s - Oxford St - the name was lost and no streets are named after the family.
Not so The Terrace. Among those who lived in the area was long-time Masterton mayor Thomas Jordan, and following his death in 1945 the street was renamed in his honour. One other Lansdowne streets commemorates a mayor, albeit one that was never elected, indeed lost the mayoralty in the next election. AR Keir was deputy mayor to multi-term mayor William Kemp, and when Kemp died in office in 1953, Kier took his place until elections later that year, when he lost of Ted Coddington. Neither of these names, of course, reflects the original naming policy.
The recent interest in a street naming policy has followed a discussion about the need for such a policy after the recent proposal to name a street after long-serving educator and local politician John McDonald. Ironically, the Masterton District Council does have a policy, formulated in 1995, by a small sub-committee of council, headed by the same John McDonald.
John McDonald had caused a few street names to be changed. In the 1960s he was instrumental in have a small street between Queen and Dixon streets named after the near-by Harlequin Theatre. Others had pushed for the street to be named Eagle St as it ran though the grounds of the old Eagle Brewery.
In the 1970s, during his term as head of Masterton Intermediate School, he was instrumental in changing one of Masterton's worst misnamed streets, a very long street called Short St. Supposedly named after a contractor called Elijah Short, the street stretched from South Rd across High St to what was then called the Kuripuni Railway Station (now Solway) on Ngaumutawa Rd.
When the York St/Short St intersection was reconstructed a competition was held among the pupils of Masterton Intermediate School for new names and, perhaps unsurprisingly, they suggested the central portion, between High St and York St, should be called Intermediate St, while from Pownall St to Ngaumutawa, where the road crests the hill, it should be named Hillcrest St. The small portion of the street remaining between South Rd and High St kept its now fitting name of Short St.
John McDonald was also a guiding hand when we produced Street Stories - How Masterton's Streets Got Their Names back in 1998, and contributed the foreword.