The sketch art of Sister Maria Innocentia Hummel began to appear in the 1930s in Germany and Switzerland, mostly pastoral drawings of children. The German art publisher Ars Sacra was involved in the early popularization of the art on postcards. Hummel's "art cards" became popular throughout Germany catching the eye of Franz Goebel, porcelain maker and head of W. Goebel Porzellanfabrik. Goebel acquired rights to turn Hummel's drawing into figurines, producing the first line in 1935. The figurines were introduced at the Leipzig Trade Fair, a major European show for the industry. Goebel was known for presenting new and novel products that attracted American distributors. By the end of the year, 46 M.I. Hummel motifs were on the market. After the end of World War II, the popularity of Hummel figurines grew as American soldiers stationed in West Germany began sending the figurines home as gifts. Nostalgia associated with the figurines and the U.S. soldiers buying them led to Hummel figurines becoming a popular collector's item. As travel to Europe became more commonplace, the figurines, with their folkloric appearance, were often purchased as souvenirs. A vibrant speculator market in Hummel figurines developed in the 1970s, and Hummel figurines skyrocketed in price.