Archaeological evidence for the use of wool felt in a burial tomb comes from the Altai Mountains in Siberia. Dating from around 600 BC, the permafrost miraculously preserved some huge pieces of wool felt whose purpose is unknown, but their presence in the tomb suggests some ritual significance.
There is an historical precedent for the use of woollen shrouds closer to home. In 1666 an English law was passed to stimulate the wool trade – the dead had to be buried in woollen shrouds or risk a fine if they used flax, hemp, silk, or gold & silver thread.
I found the Ikat weavers of the Sumba Islands in Indonesia particularly inspiring. These incredible funeral shrouds take at least 3 months to weave.