Complex sentence: Resurrectionists were commonly employed by anatomists in the United Kingdom, during the 18th and 19th centuries, to disinter the bodies of the recently deceased because there was a severe shortage of cadavers for anatomical research.
Split into simpler sentences: Resurrectionists were commonly employed by anatomists in the United Kingdom, during the 18th and 19th centuries, to disinter the bodies of the recently deceased. Their role became popular due to a severe shortage of cadavers for anatomical research.