I gave myself permission to perform a genealogy happy dance when I learned that FamilySearch had digitized county records from San Mateo County, California. My 3x great-grandfather Owen O’Neill was an early settler of Belmont township in San Mateo County, which lies about 20 miles southeast of San Francisco.
The county records for San Mateo on Familysearch include marriage intentions, naturalizations, deeds, patents, homesteads, military service discharges, and coroner’s reports from 1851-1991. Indexes for land records are available in this collection and include grantor, grantee, and those that consolidate both grantor/grantee. The three types of indexes are in bound volumes and each covers a different range of dates. The first 10 volumes of land records, dating from 1856-1910 are indexed in the consolidated grantor/grantee indexes. Deeds in these volumes are indexed by the first letter of the surname, not in exact alphabetical order. Researchers have to scroll through each image until they reach the desired entry. The indexes consolidating both grantors and grantees in the first 10 volumes are the ones that led me to the deeds of Owen O’Neill and his family.
On 29 Dec 1858, Owen O’Neill purchased one acre portion of the Rancho called Tidgas Ramelio from Soledad O de Aigiuello, Jose Ramon Aigiuello of Santa Clara County and Simon Montserrate (S.M.) Mezes of the city of San Francisco. The one-acre tract of land ran along the eastern side of the county road to San Francisco, still known today as Old County Road in Belmont. 
Almost three years later, Owen O’Neill added to his landholdings substantially. On 29 May 1861, he purchased 30 acres of swamp and overflow land for $75.00. This swamp land became known as “O’Neill’s Slough” and it was on this property that he erected a pier and rented docking space for boats used by local duck hunters.
The next reference to Owen O’Neill in the land indexes brought me to the distribution of his estate. I was intrigued to find probate records in the deed books, for I had not seen this before. The probate file had been copied in by the register of deeds several months after their actual appearance in court. Owen died on 28 May 1871 intestate and it would be some years before the estate was finally settled. On 13 May 1878, his wife Ellen administrator filed in probate court the final account and petition for Owen’s estate, which would be heard before the probate judge on 2 Jan 1879. The record names five children of Owen, including Ellen Maria, Matthew, Katy, Eugene, and William O’Neill. Owen’s wife received one half of the land, while the children split the other half, amounting to one tenth each of his estate. 
Owen’s wife Ellen died 1 Aug 1883, and the children went back to probate to resettle the estate of Owen O’Neill. The register of deeds had once again copied the settlement of the estate, held in San Mateo County Superior Court on 31 Jan 1884. My great, great grandfather, Matthew J. O’Neill, himself a land speculator, was named administrator of the estate. It was decided in Superior Court that half of the O’Neill estate would be equally shared among the five children named Ellen Greichen, Matthew J. O’Neill, Eugene O’Neill, Katy F. O’Neill, and William J. O’Neill. The big clue from this document is Owen and Ellen’s first daughter by this time had married and eventually led me to who her husband was, a man named William Greichen. 
Two weeks later, on 15 Feb 1884, the O’Neill Family returned to Superior Court where the estate of Owen’s wife, Ellen O’Neill, was settled; leaving the daughters Ellen Greichen and Katy Francis O’Neill to split the other half of the O’Neill property.
Local history sources show that the O’Neill Slough or swamp land bought by Owen in 1861 went through many uses in the following generations. Owen’s son, Eugene, a grocer in Belmont, kept the landing going and in addition built shelters for duck hunters and sportsmen, as well as bathhouses for locals seeking a little R&R. The Belmont shoreline became a popular spot for locals and by the 20th century, shelters became permanent residents and led to establishing a new village in Belmont, known as “Shantytown.” Ironically, Belmont’s Shantytown wasn’t home to vagrants and paupers, but some of Belmont’s most respected citizens. Still, the marsh became a hot spot for smuggling and bootlegging in the 1930s and by the 1950s, had altogether disappeared. The connection to duck hunters made all the more sense now, since I knew for a long time that my great-grandfather Mervyn O’Neill was an avid sportsmen. This picture below shows him on one of his hunting excursions. I am more than confident he spent a fair amount of time shooting game on the O’Neill property.
Locating deeds and tracking the real estate property within families is an important research direction for genealogists to take. It reveals some of the family dynamics, as well as the identities and any married names of children who appear in court. Combing through the land indexes, there are many more deeds concerning Owen’s children, particularly my great, great grandfather Matthew. We shall see what more genealogical treasures can be found digging through San Mateo’s county records.
 San Mateo County, California Deeds. Book 1, page 472: accessed at FamilySearch, “San Mateo County Records, 1851-1991.”
San Mateo County, California Deeds. Book 4, page 101: accessed at FamilySearch, “San Mateo County Records, 1851-1991.”; Paul D. Buchanan “O’Neill Slough recalls Belmont’s Shantytown,” The Daily Journal (San Mateo, California), 29 July 2002: accessed at http://www.smdailyjournal.com/articles/lnews/2002-07-29/oneill-slought-recalls-belmonts-shantytown/15601.html
 San Mateo County, California Deeds. Book 32, page 127-30: accessed at FamilySearch, “San Mateo County Records, 1851-1991.”
 San Mateo County, California Deeds. Book 37, page 205-6: accessed at FamilySearch, “San Mateo County Records, 1851-1991.”
 San Mateo County, California Deeds. Book 37, page 223-4: accessed at FamilySearch, “San Mateo County Records, 1851-1991.”
 Paul D. Buchanan, “O’Neill Slough Recalls Belmont’s Shantytown.”
Appendix – Past Blog Posts and Sources on O’Neill Family
“Obituary of Owen O’Neill and wife Ellen Russell,” posted 9 Oct 2015.
“More Clues to Owen O’Neill’s Seafaring Past and Life in California,” posted 15 Jul 2015.
“Further Investigating My O’Neill Ancestors from San Francisco Bay,” posted 18 Jan 2015.
Copyright (c) 2016 Jake Fletcher.
Jake Fletcher, “Land Records and Estate Files for Owen O’Neill of Belmont, California.” Travelogues of a Genealogist, posted 12 Mar 2016. https://fletcherfamilytree.wordpress.com/2016/03/12/land-records-and-estate-files-for-owen-oneill-of-belmont-california