According to the best evidence I have, applications for pensions were made for 1227 men (61% of the regiment) (by either the men themselves or their dependents), and about 91% of them received pensions. (Was William Wightman's widow the first applicant in the regiment? She applied on 29 August 1862, and received widow's pension #413.)
In at least two cases, spouses received pensions to which they were not entitled, because they had remarried. In one of those cases, the pension examiner recommended prosecution; in the other the spouse genuinely believed she was not married.
Charles T Cotton was the examining clerk for most early pension applications by dependents of men who served in the 91st.
The Act of July 14, 1862 provided pensions for anyone disabled since 4 March 1861 as a result of wounds or illness contracted while in the service and in the line of duty. For total disability, it allowed eight dollars per month for privates, with the amount increasing as the rank increased, to a maximum of thirty dollars per month for lieutenant-colonels (and any higher ranks). Partially disabled men received proportional pensions. Widows and orphaned children less than sixteen were entitled to the same amount the soldier would have been entitled to if he had been totally disabled. Finally, mothers, or orphaned sisters, dependent on the soldier for support could claim if the soldier did not leave a widow or legitimate children.
The act of 25 July 1866 increased the pension for dependent minor children by $2 per month, and made other changes.
The Act of 25 January 1879 changed the date from which certain pensions started, effective retroactively.
The act of 3 March 1879 changed the effective date of pensions.
The Act of 19 March 1886 increased the pension rate for dependents.
The Act of 27 June 1890 significantly expanded the coverage. Anyone who had served at least ninety days and been honorably discharged, and was unable to earn a living by manual labor, was entitled to a pension of six to twelve dollars per month, as long as the inability was not due to his own vicious habits. Similarly, widows were eligible for pensions of eight dollars per month whether or not their husband's death was a result of his service, etc.
The Joint Resolution of 15 February 1895 extended pension eligibility to appropriate members of the Missouri State Militia and the Provisional Missouri Militia.
The Act of 9 May 1900 amended the act of 1890.
The Act of 3 March 1901 allowed remarried widows to resume their pension if their subsequent husband died, or they were divorced on their own application and without fault on their part.
The Joint Resolution of 1 July 1902 allowed soldiers not honorably discharged to receive a pension if they had been honorably discharged from subsequent service (with several additional conditions).
The Joint Resolution of 28 June 1906 allowed soldiers not honorably discharged to receive a pension if they had been honorably discharged from subsequent service (with several additional conditions).
The Act of 6 February 1907 provided pensions for all men who had served at least ninety days and been honorably discharged and were at least sixty-two years old.
The Act of 19 April 1908 increased the rate of pension for dependents, and extended eligibility to widows whether or not their husbands' deaths resulted from their service.
The Act of 11 May 1912 made the amount of the pension provided because of age depend also on the length of time the soldier had served.
The Act of 8 September 1916 increased the pension for widows, and allowed remarried pension to receive a pension after the death of their later husband.
The Act of 1 May 1920 equalized various pension rates.
The Act of 3 July 1926 increased the rates.