Siobhan Senier, beloved spouse, daughter, sister, and friend, died Thursday, July 16, 2026, surrounded by her family.

Born in Boston, Massachusetts, on June 26, 1965, to John and Phyllis Senier, Siobhan lived a life of learning, teaching, activism, and loving. She earned her bachelor’s degree from Bowdoin College, followed by a master’s and Ph.D. from the University of Illinois, Urbana-Champaign. Her scholarship focused on the literature of New England indigenous peoples. She wanted to introduce her students to Native American literature, but was frustrated because so little of it was widely available. This motivated her to create an anthology of writings from 12 New England tribal nations, a task she approached in a spirit of collaboration. She partnered with community editors from tribal nations to develop the anthology. Together, they made selections and wrote headnotes to contextualize the writings. The resulting book, Dawnland Voices, includes excerpts of historical documents from the precolonial era to works of contemporary poets and writers.

Music was a hugely important part of Siobhan’s life; she played the piano, the flute, the penny whistle, the fiddle, and the banjo. When the Bowdoin College jazz band needed a baritone saxophone player, she gamely jumped in. In the last years of her life, she learned the trombone, and played with the Leftist Marching Band of Portsmouth, New Hampshire, and the School of Honk in Somerville, Massachusetts.

After retiring from 25 years of dedicated teaching and scholarship as a University of New Hampshire professor, Siobhan devoted herself full-time to climate justice–a cause to which she had long been committed–serving as the Executive Director of 350 New Hampshire.

Siobhan is survived by her husband, Greg Tillman of Epping; her father, John Senier of Andover; her sister Laura Senier and brother-in-law Ken DelPapa of Natick; and her sister, Amy, of Santa Fe. She is also survived by many, many loving friends, collected over the years by a generous and empathetic heart, a love of cake and good food (and cake), and her deep capacity for sharing joy.

Siobhan was in the end successful during her life with struggles against addiction and depression, one day at a time. And in her memory, if you or anyone you know has similar struggles, her family would encourage you to look for help where you can, whether a doctor or a support group.

A service will be held at 3:00 p.m. on Saturday, June 25, 2026 (calling hours 2:00-3:00 p.m.) at the Cremation Society of New Hampshire, 243 Hanover Street, Manchester, NH 03104.

In lieu of flowers, donations can be made to either of the following:

350 New Hampshire 1 Washington St, Suite 3123 Dover, NH 03820 https://www.350nh.org/donate

Tomaquag Museum of Rhode Island 390A Summit Rd Exeter, RI 02822 https://www.tomaquagmuseum.org/

Assisting the family with arrangements is the Cremation Society of NH, Manchester. To view Siobhan's Online Tribute, send condolences to the family, or for more information, visit www.csnh.com.