Elisabeth De Saedeleer was born on 27 August 1902 in the Dutch-speaking Belgian town of Sint-Martens-Latem, near Gand. Her father, Valerius De Saedeleer (1867-1941), was already a well-known painter. 
When the First World War broke out, the De Saedeleer family was one of the many souls who had to leave their country to take refuge in Great Britain. A policy of welcoming Belgian artists, known for their creativity and specific skills, was developed. Professor Fabrice Polderman, based in Cardiff, proposed to welcome these artists to Wales. Under the patronage of David Davies of Aberystwyth (Baron Davies of Lllandinam from 1932), the families of the artists Minne, De Saedeleer and Van de Woestjine settled in Aberystwyth. The De Saedeleer family settled in a comfortable house called Ty'nlon in Rhydyfelin where Valerius was able to paint, an activity that allowed him to integrate himself into the Aberystwyth art scene and to make a living from his art, which was particularly appreciated by the locals. In 1918, he was appointed director of the Arts and Crafts Museum, which he planned to link with University College Aberystwyth. 

I work quite well here. I have my family with me in a beautiful country and a beautiful house,
I'm as happy as I can be, away from Flanders and this horrible war. - 
Valérius De Saedeleer

        This environment is conducive to the development of a craft vocation in Maria, Maarie-Jozef, Monica and finally Elisabeth, the five daughters of Valerius. It was here that they learned weaving techniques and met one of the former employees of William Morris. Elisabeth met his daughter, Mary (or May) Morris (1862-1938), who taught her all about traditional tapestry weaving techniques. The productions of the De Saedeleer sisters were a resounding success, so much so that the family considered setting up a weaving school. From 1919 onwards, they received a multitude of orders and worked almost independently. However, the project of a weaving school-workshop ran out of steam, lost its main supporters and the De Saedeleer family finally returned to Belgium in 1921. The idea of founding an arts and crafts centre in Etikhove had not left them. The town became one of the most important weaving centres of the modernist era with the official establishment of the weaving workshop "Société de Tapis d'Art De Saedeleer et Cie", also known as "Studio Saedeleer", on 12 September 1926, in collaboration with the brothers Luc and Paul Haesearts. The tapestry school is adjacent to the Valerius workshop. Elisabeth played an important role in the school and in her own studio she transferred her father's drawings, as well as those of other artists, to the tapestry cartoons. The workshop was later transferred to Brussels.

        Elisabeth De Saedeleer's workshop - located in the Art Deco style Basilica of the Sacred Heart in Koekelberg - achieved considerable fame in the 1920s and 1930s. There she produced bright and colourful tapestries and carpets based on designs by artists such as Ossip Zadkine, Michel Seuphor, Marc Chagall and André Lhote. In 1927, she was appointed to teach in the textile art department of the Institut supérieur des arts décoratifs de Bruxelles La Cambre. Elisabeth was very concerned about the future of her profession and wrote in an article she dedicated to the weaving technique : 

In order for the art of carpet weaving to regain the full development it had in the past, it is necessary that an elite of people, educated by good taste, can appreciate and protect this work. (...)
The craft is in danger of disappearing (...)
It is necessary that this profession be gratifying and rewarding and nothing should be neglected to encourage young people to this wonderful activity.