He was the last relevant leader of the group; by the time of Nummy's death, the Kechemeche had largely either migrated westward, integrated into colonial society, operated as independents, or perished.
Nummy's life is not well documented; what little is known about him is what was written about him by the colonial settlers of New Sweden and New Jersey, rather than the Lenape themselves.
What is documented is that Nummy acted as a peace broker and trader, a contact between the European settlers and the Lenape.
Some sources indicate he was a chief of all the Unalachtigo branch of the Lenape rather than merely of the Kechemeche, although European settlers routinely overestimated the sway of leaders willing to work with them in American Indian - colonist relations, so this belief may not have been well-grounded.
[2] Nummy had a sister, Snowflower, and according to some traditions, she married an English missionary named Benijah Thompson.