A painter, etcher and watercolourist, Barend Hendrik Thier was born near Münster and studied with his brother, the glass painter Evert Their. (Another brother, Hendrik Their, was a draughtsman and art teacher.) Barend Thier was active mainly as a painter of decorative wall-hangings and landscapes, but also made finished gouache and watercolour drawings as independent works of art for sale to collectors.

In the 1780s Thier also produced a series of 155 botanical watercolours of rare plants and flowers, cultivated at an estate garden known as ‘Amerika’, outside Leiden, which were commissioned from the artist by the owner of the garden, Isaac van Buren. A number of sketchbooks by Thier have survived - in the Kupferstichkabinett in Berlin, the Teylers Museum in Haarlem and the Louvre - while other drawings by the artist are in today in the collections of the British Museum, the Rijksprentenkabinet in Amsterdam, the Kunsthalle in Bremen, the Musée Royaux des Beaux-Arts in Brussels, the Graphische Sammlung in Frankfurt, the Kunsthalle in Hamburg, the Gemeentearchief and the University Library in Leiden, and elsewhere