Searching for Andrew Broughal (b. 1830) of Wicklow / Ellen Mullaly (b. 1836) of Unknown.

Have you located death certs for Andrew & Ellen - these could include the names of parents which would help confirm or rule out any potential matches. I'm assuming that your Broughals were Catholic, as all with the surname are shown as this denominatiom on the 1901 census of Ireland.

Records for most Catholic parishes in Co. Wicklow are included in the National Library of Ireland register images, and transcribed on FindMyPast and Ancestry. A search of baptisms shows just one close match around the right time in Co. Wicklow - an Andy Brohil baptised 10th January 1830 in the parish of Ballymore Eustace (see the right hand page - about half way down). The parish covers parts of counties Wicklow and KIldare. The parents are shown as Dennis Brohil and Judy Nugent. The sponsors (godparents) seem to be another Andy Brohil & Mary Brohil.
 

Unfortunately no luck on the death certificates. They both died right before Pennsylvania started keeping death certificates statewide in 1906. At some point this winter I'm hoping to make it up to Pennsylvania as my understanding is that counties began keeping them in 1893, so there might be something for Ellen, but it'd only be held at the county courthouse. That said, they were definitely Catholic, so I can confirm that. It's also worth mentioning that while there's no Judy I've found among his children, the second eldest of his kids that I could find is a Dennis Joseph, and that name also pops up several times among his grand-children. There are also numerous Marys and Andrews, including among his children, so those names definitely are in the family as well. Are there any other ways to confirm this link that spring to mind. Also, thank you for the help - I appreciate it as I'm very much finding my way in the world of genealogy and how it works in Irish history.

I'd say that 1830 baptism is a very likely match for your Andrew - Broughal and it's variants (Brohile, Broughall, Broughill etc)  is not a common surname, and Co. Wicklow has good coverage of Catholic records for the 1830s.

The Tithe Applotment records include a good match for Andy's father Denis/Dennis sharing in Slievecorragh townland in Hollywood civil parish, which is one of the civil parishes covered by Ballymore Eustace Catholic parish, this section of the Tithe records is dated 1834.  One of the townlands in Hollywood civil parish is named 'Broughills Hill'..

Not to jump to conclusions, but it looks like there are a number of Nugents also listed in the applotment records for Slievecorragh you sent.

I just took a quick look and there's a Judith Nugent born to James and baptized in Nov of 1811. It looks like a couple of the Nugents in those records could be 'Jas. Nugent' so this looks pretty promising. Any idea where I can dig up more info on 'Broughills Hill'? And it seems like censuses are sort of thin that far back - any idea if there's anywhere else I could connect these people or build out a better picture of the whole family?

There are a few census substitutes available for the mid and early 1800s, Griffith's Primary Valuation and the Tithe Applotment Books -  some fragments of early census returns survive, but none that I know of for this area. Griffith's Valuation for Broughills Hill townland is dated 1854 and shows nine properties - six of which have the surname Broughill. The earlier Tithe Applotment books for Broughills Hill dated 1834 show just under half the properties as having surname Broughhill, and just over twenty in total in the parish with the surname.

The origins of the surname Broughall/Broughill appear to be uncertain - e.g. MacLysaght's entry for the surname is as follows "There are references to this [sur]name in Irish records from the fourteenth century, mainly in east Leinster, the derivation is uncertain".  It's possible that the the townland is named after the family ... or vice versa..

Broughills Hill townland is in Hollywood civil parish Co. Wicklow and there are some details on the area included in the entry for the parish in Lewis Topographical Dictionary of 1837, also the Placename Database includes an entry for Broughills Hill townland.
 

for reference - from a posting on another Forum :

from Ballymore Eustace RC baptism registers (NLI/FMP and RootsIreland) :

James (1) Braughal bapt. 1st March 1826
[Andrew 10th Jan 1830]
James (2) Braughal bspt. 25th August 1830
Mary Brawghel bapt.3rd March 1833
Dennis Broughil bapt. 25th March 1826

mother's surname not recorded in the registers during this time - one of the godparents to James(1) and James (2) is a Nugent. The first James likely died when young..

a very small gap in the between Andrew and James(2)....