Catherine McAuley and her companions were social workers in Ireland. After being orphaned, Catherine had worked as a maid to a rich couple. Upon their deaths, Catherine inherited their fortune. She put the funds to good use, working among the poor. The house on Baggot Street in Dublin was purpose-built for works of mercy, basically on a convent floorplan.
Her local archbishop liked what he saw, and asked Catherine and her companions if they were attracted to becoming a religious congregation. They were, and set out to write down what they had been doing. The archbishop asked the Presentation Sisters to host the Founder's Novitiate:
https://presentationsistersne.ie/ne-locations/dublin-georges-hill/
Photos of the former Convent:
https://www.buildingsofireland.ie/buildings-search/building/50070310/focus-ireland-georges-hill-halston-street-dublin-7-dublin
"The Walking Sisters" were called such because they interacted with society. For more history:
https://www.sistersofmercy.org/about-us/our-history-mercy-heritage-center/
There is also a video regarding the Sisters of Mercy habit, but I am unable to get the URL.
Mercy presence in the US:
Pittsburgh, PA:
https://www.sistersofmercy.org/pittsburgh-mercy-founders/
Building shown in Dehey:
Mansion shown on the left in Dehey burned down.
Scroll to bottom of page, then enlarge photo. Click the blue pin over the H-shaped building. Description of the Convent of Mercy will pop up:
https://www.carlow.edu/admissions-aid/visit-carlow/virtual-tours/
New York, NY:
St Catherine's Convent:
https://www.periodpaper.com/products/1893-print-st-catherines-convent-madison-avenue-nyc-original-historic-image-009567-ny2-090
St Catherine's Academy:
https://www.scahs.org/apps/pages/index.jsp?uREC_ID=1564396&type=d&pREC_ID=1692127
Novitiate:
https://www.cardcow.com/141620/tarrytown-new-york-sisters-mercy-home/
Chicago, IL:
Building shown in Dehey:
Academy of St Xavier:
http://www.illinoishsglorydays.com/id771.html
Apparently, a newer building on the site:
(Part of) Hales Franciscan up for sale:
https://chicagodefender.com/historic-hales-franciscan-puts-a-portion-of-its-bronzeville-campus-up-for-sale/
Mother McAuley Liberal Arts High School:
https://www.mothermcauley.org/about/history
Providence, RI:
"When Rhode Island Received Mercy":
http://smallstatebighistory.com/rhode-island-received-mercy/
Building shown in Dehey:
Alumnae Association:
http://stxavieralumnae.org/history.html
E-Yearbook:
http://www.e-yearbook.com/yearbooks/St_Francis_Xavier_Academy_Xavier_Yearbook/1955/Page_1.html
St Xavier Academy:
https://oldpvd.com/markers/772
Little Rock, AR:
Mt St Mary Academy:
http://mtstmary.edu/about-us/history-and-founders/
Hartford, CT:
Historical marker for first Convent:
https://www.hmdb.org/m.asp?m=151939
Building shown in Dehey:
Scroll down to middle picture of cathedral burning. Convent shown left of the cathedral.
https://www.hartfordcathedral.org/history.html
Convent was torn down after the cathedral burned.
Burlingame, CA:
Building shown in Dehey:
https://sistersofmercyburlingame.com/history/
Baltimore, MD:
Building shown in Dehey:
Mt St Agnes Academy:
https://en.wikipedia.org/wiki/Mount_Saint_Agnes_College
Brooklyn, NY:
Convent closed due to structural/foundation issues:
https://www.brownstoner.com/brooklyn-life/closing-bell-tour-a-former-convent/
Webster Groves, MO:
Building shown in Dehey:
Laclede Groves Assisted Living:
https://www.lssliving.org/communities/laclede-groves-st-louis/
Vocational Link at end of last post.