This is the tombstone of Martin Geier, located in row 8 of Zion Lutheran Cemetery, Schumm, Van Wert County, Ohio. The marker is inscribed:
Geb. Den 25
Gest den 22
86 J, 2 M, 27 T
Johann Martin Geier, born 25 Sept 1816, died 22 Dec 1902, age 86 years, 2 months, 27 days.
According to the death and burial records of Zion Lutheran Church, Schumm, “Martin” Johann Geier was born 25 September 1816 in Oberaspach, District Schwabisch Hall, Wuerttemberg. His surname was sometimes spelled Gaier in Zion’s records but for this post I am using the Geier spelling. 
Martin Geier married Margaretha Grund 8 February 1853 at Zion.  Margaretha was the step-daughter of H.G. [name unreadable]. Martin and Margaretha had several children and she died during childbirth on 15 October 1861.
Known children of Martin and Margaretha (Grund) Geier:
Rosina Elisabetha Geier (1854-1914), married John Weinmann
Johann Eberhardt Geier (1857-1857)
Catharine Rosine Geier (1857-1922), married Henry Roehm 
Johann Jakob Geier (1859-)
Johann George Geier (1861-1861)
The Martin Geier family in 1860: Martin, 44; Margaret, 30; Rose Ann, 5; Catharine, 3; and John, 4 months. Martin was a farmer. Both Martin and his wife Margaret were born in Wuerttemberg and their children were born in Ohio. 
Martin Geier’s second marriage was to Susanna Fischer and they were married at Zion Schumm on 8 May 1862. Martin and Susanna had two children, George Christoph Jacob Geier (1863-1942) and George Geier, born 5 May 1865, died 31 August 1865. Martin’s second wife Susanna (Fischer) Geier was born 21 August 1842 and died 1 September 1865, the day after their second son died. She was 23 years old.
Martin Geier’s third marriage was to widow Eva Katharine (Windsheimer) Hoffmann, the widow of Johann Hoffmann (1824-1865).  Martin and Eva Katharine were married at Zion Schumm on 8 May 1866 and they had at least two children, Maria Geier, born 22 February 1867, married Michael Kuehm, died 14 April 1944; and Magdalena Geier, born 11 October 1869, married Willis Putman, died 21 June 1921. Martin’s third wife Eva Katharine (Windsheim) Geier died from a back injury on 1 January 1870, at the age of 39 years, 4 months, and 3 days.
In 1870 widower Martin Geier, five of his children, and John and Magdalena Bienz and their family all resided together: Martin Geier, 55; Rosina Geier, 15; Catharine Geier, 12; Jacob Geier, 7; Mary Geier, 3; Magdalena Geier, 3 months; John Bienz, 47; Magdalena Bienz, 35; John F Bienz, 17; George E Bienz, 15; Rosina C Bienz, 13; Anna BC Bienz, 11; John JC Bienz, 9; Henry W Bienz, 5; and Mary Bienz. 
Martin Geier’s fourth marriage was to Maria Ursula Rohr, married 13 November 1870. Maria Ursula Rohr was born 15 August 1815 in Ottenheim, Oberant Luhr, Wuerttemberg. She died of cholera on 23 July 1890, aged 74 years, 11 months, and 22 days.
In 1880 the Martin Geier family lived in Jefferson Township, Adams County, Indiana: Martin, 63; Mary, 64; Jacob, 17; Mary, 13; and Lena, 10. Martin was a farmer. 
By 1900 widower Martin Geier had moved back to Willshire Township and was living with the Henry Roehm family, which was his daughter Catharine’s husband and children: Henry Roehm, 47; Catherine Roehm, 42; Elmeda MR, 19; Bertha A, 18; Della G, 16; Nora E, 13; Hilda H, 11; Louisa H, 10; Alvina M, 8; Theodor H, 5; Edward AM, 2; and Martin Geier, 84. This enumeration indicates that Martin immigrated in 1852. 
Martin Geier died of old age on 22 December 1902, at the age or 86 years, 2 months, and 27 days. He was buried on the 24th.
The deaths Martin Geier’s four wives were recorded in Zion Schumm’s records and they were very likely buried in Zion’s cemetery. However, it appears that none of their tombstones have survived.
Additional research could certainly be done on these intertwined families.
 Most of the vital information about Martin Geier, his marriages, and his children are from Zion Lutheran Church, Schumm’s records.
 Zion Lutheran Schumm marriage record gives her name as Eckert at the time of their marriage.
 Johann Eberhardt Geier and Catharine Rosine Geier were not twins. Johann was born in January 1857 and Catharine Rosine was born in December 1857.
 1860 U.S. Census, Willshire, Van Wert, Ohio, p.425, dwelling 1064, family 1058, Martin Gier; digital image by subscription Ancestry.com (https://www.ancestry.com/search/collections/7667/ : viewed 18 Oct 2021).
 Eva Katharine had five children with her first husband Johann Hoffmann:
Christian Hoffmann/Hofmann (1854-1919), married Lena Schinnerer
Rosina “Elisabeth” Hoffmann (1857-1913), married Abraham Pflueger
Johann George Hoffmann (1859-1942), married Malinda Miller
Christian Adam Friedrich Hoffmann (1861-1864)
Hannah Rosine Magdalena Hoffmann (1863-?), married Fredrick Glessing
 1870 U.S. Census, Willshire, Van Wert, Ohio, p.439B, dwelling 135, family, Martin Gire; digital image by subscription Ancestry.com (https://www.ancestry.com/search/collections/7163/ : viewed 18 Oct 2021).
 1880 U.S. Census, Jefferson, Adams, Indiana, ED 133, p.54A, dwelling & family 122, Martin Guyer; digital image by subscription Ancestry.com (https://www.ancestry.com/search/collections/6742/ : viewed 18 Oct 2021).
 1900 U.S. Census, Willshire, Van Wert, Ohio, ED 98, p.11, dwelling 27, family 222, Henry Roehm; digital image by subscription Ancestry.com (https://www.ancestry.com/search/collections/7602/ : viewed 18 Oct 2021).