Category Archives: Family Tree

Plotting the map’s family tree

The – with 13 A3 pages very wide – family tree (Family Tree of Emigrated Buehrers) shows all persons that emigrated to the United States including their ancestors as well as their immediate relatives. Persons are aligned horizontally by generation, with oldest generations on the top. Squares denote males, circles females and triangles marriages. Persons represented by black line symbols are shown on the map whereas those with grey line symbols are not. Otherwise symbology follows the one for the map, i.e. line styling indicates category and colours show common male ancestors.

Family Tree of Emigrated Buehrers - Detail
Detail of the family tree of emigrated Bührers

Data for the family tree was prepared in the project’s PostgreSQL database stripping irrelevant persons and families. The family tree was drawn in yEd ( in “Family Tree” mode and styled via Properties Mapper.

The methodology – preparing genealogical data for maps

The production of the map showing the emigration of Bührers from Switzerland to the United States relied on the following, largely self-developed sequential steps:

  • Normalization, completion and geocoding of places used for family and persons events
  • Identification and categorization of in-scope persons, notably persons born as Bührer or name varieties such as Buehrer (“Named”), spouses (“Married”) and their children/grandchildren (“Descendant”) that have different family names
  • Constructing a sequence of geocoded events for a person’s life, also considering childbirth for women. In case geocoded events lacked dates a natural sequence was assumed, i.e. birth followed by marriage, childbirth, death and burial.
  • Determination of an emigration/residence status relative to Switzerland, the US or third countries. Of particular interest were those that emigrated to the US as well as confirmed or assumed US residents
  • Determination of a common male ancestor for all Bührers that emigrated or have lived in the US and the generation relative to him
  • Deriving a family status for emigrants, i.e. whether emigrants emigrated as single, with their spouse or family
  • Assignment of persons to a time period (generations prior/beyond 1880) based on known birth years, ensuring a consistent assignment of couples and siblings to the same period
  • Construction of migration path segments following the sequence of geocoded events
  • Aggregation of migration paths per county and time period, including aggregated indicators such as the category of in-scope person with Bührer prevailing and the minimal generation involved
Geocoding places in MacFamilyTree
Geocoding places in MacFamilyTree
Sample PostgreSQL script
Sample PostgreSQL script (categorization of in-scope persons)

Mapping the Emigration of the Bührers from Switzerland to the United States

In the second half of the 19th century many farmers emigrated from the rural communities of the Swiss canton of Schaffhausen, mainly due to a local agricultural crisis and better economic prospects elsewhere. There were emigration peaks around 1850, 1870 and in the 1880’s with a large majority of emigrants heading to the United States. From 1868 to 1890 an equivalent of more than 10% of the canton’s population had left, a large number for Swiss standards at the time.

Among the emigrants were many Bührers from the small hamlets of Bibern, Hofen, Opfertshofen as well as from Herblingen and Stetten in the Reiat region. Originally immigrated from southern Germany the Swiss Bührer at large remained constrained to that tiny corner of Switzerland, which greatly facilitates genealogical research.

Emigration of Buehrer to the United States - Map 1
Emigration of Buehrer to the United States – Map 1

The maps shows the Bührers’ emigration to the United States (Map 1) up to the 1880s and subsequent internal migration up to now (Map 2). Almost all of them initially immigrated to a small area in northwestern Ohio around the city of Archbold in Fulton County; some of them migrated further west to Kansas, Texas or the Pacific Northwest.

In order to provide the necessary historic context Map 1 shows historic state boundaries, population density as well as the railway network (the main mode of transportation for Swiss emigrants) at 1870, the heyday of the Bührer emigration.

Emigration of Buehrer to the United States - Map 2
Emigration of Buehrer to the United States – Map 2

A legend explains the symbology.