Sources of Land Ownership
- Abstract of Title
If you own the property, you (or your mortgage holder) may have an abstract of title, which lists the landowners from the U.S. government down to you. Note that this is a record of the land, not the buildings. There may be a phrase such as "and all buildings thereupon." There are also less obvious clues, such as a major jump in the value in just a few years, which might indicate a new structure.
- Register of Deeds
If you do not have the abstract, the chain of ownership can be recreated at the Register of Deeds office in the Winnebago County courthouse. Each transfer of property after the initial purchase from the U. S. government is recorded at the Register of Deeds office for Winnebago County. Transactions are recorded three ways: by grantor (seller), by grantee (buyer), and by tract or legal description of the property. Search by legal description is the easiest. Although the staff will show you where the books are, they cannot do the search for you. Be prepared to spend some time in this search; you have over 150 years of history to cover.
- Using the Records of the City Assessor's Office
When you click the link to the City Assessor's office , the form is set for a search by owner's name. The system requires the exact spelling of the last name to work correctly. You may find it easier to use the address search.
When your search yields a result, click the Parcel Number for more information. Information included is parcel description (the street address), owners, lot size, and legal description. On the menu to the left, you can click the Main Building option for a description, including age. Often this will simply be listed as 50+ years. Click OBY for "Other buildings and yard improvements" to find out about garages or similar buildings.
Should you pursue your search in old assessment or tax rolls, you will need the legal description.
- Using Property Tax or Assessment Rolls
Property tax and assessment rolls describe the land and buildings at a certain location. They were produced by each municipality (city, village or civil town) and are organized by legal description. You must have the legal description to use these rolls. This description is on the tax bill if you are the property owner. Otherwise, for the City of Oshkosh, use the website for the Assessor's office  to get this information. Plat maps can be used to determine the legal description of rural areas. It will be easier if you have an approximate date for the construction of a building. One roll may describe the building as one story of wood, the next describes a larger two-story brick home. The brick home was built between the two assessment dates. Remember that a home may have been in the Town of Algoma or Town of Oshkosh when it was built, and later been annexed to the City.
The old assessment rolls for the City of Oshkosh are at the Oshkosh Public Museum . You will need to make an appointment with Archivist Scott Cross to use these. For rural area, the rolls are at the Area Research Center , UW-O Polk Library. Contact Archivist Joshua Ranger.
Additional information on finding property tax rolls and assessment lists and what information they will provide can be found on the Wisconsin Historical Society's web site.