Family tree archivist Simon, of Brighton, began the search in 1974 as older members of the family managed to give him details, photos and letters so he could search and collect all the names.
And, to date, Simon has found family going back to 1816 in Brody and Austria.
Descendants have produced 300 members and are scattered all over the world, including the UK, America, Austria, Australia, Israel, Brazil, Denmark and Argentina.
The Piczenik and Wunsch families were involved in textiles in Manchester via market stalls, factories and shops.
Simon said: “We have records of their businesses. People who attended the reunion were fascinated to see the family tree charts which included all the branches from all over the world and many photographs of the huge families since 1890 to present day.”
The reunion was held in Salford, as 80 per cent of the Piczenik and Wunsch families still live in the area.
If you are connected with the Piczenik and Wunsch families, email firstname.lastname@example.org