One of these is the Mortality Schedule, which contains information about persons who died in the year previous to the census day. This schedule was taken during the federal censuses between 1850 and 1900, and the special 1885 census taken in Nebraska, Colorado, Florida, and the territories of South Dakota and New Mexico. Unfortunately, the 1890 and 1900 mortality schedules are not extant. But if your ancestor is listed in a mortality schedule, you can find a wealth of information that generally pre-dates the collection of vital statistics.
The census enumerator was instructed to record information about every person who died in the 12 months preceding census day, which was June 1st in the years from 1850 to 1885. For example, in 1850 the mortality schedule should list the names of people who died between June 1st, 1849 and May 31st, 1850. Theoretically, about 13 percent of people who died between 1849 and 1880 should be included in the mortality schedule, although not everyone was included who should have been.
If you are lucky enough to find your ancestor or another relative, you can expect to find the following information: name, age, gender, color, birthplace, occupation, month & year of death, cause of death, number of days ill, etc. In 1870 the parents' birthplaces were added to the list, and in 1880 the length of time of residence and the place where the disease were contracted were added. This information can help you track an ancestor's migrations.
When you find someone listed in the mortality schedule, you can then use that information to look for an obituary, cemetery record, funeral home record, and probate record. When you search the mortality schedules, don't just look for your direct-line ancestor. If you find information about a relative it may contain clues that will help you in other research. For example, if your ancestor's sibling is listed in a mortality schedule you may be able to use the death date to find an obituary. The obituary may include information about surviving family members (including your ancestor!). Often family members were all buried at the same cemetery, or had the same physician. And if the cause of death was due to a genetic disease, it can help you trace medical histories.
It is easy to access mortality schedules. Many have been indexed, and the indexes are usually available at archives or libraries next to the population schedule indexes. The actual schedules were microfilmed and are available at National Archive branches, the Family History Library, and many state historical archives (usually just the records for that state). If someone died during the right time frame and isn't in the indexes, go ahead and search the actual schedule for the county•indexes can certainly contain errors, and it's not hard to scan the schedules themselves.
If you've never looked at a mortality schedule, give it a try; you will probably find someone who was related to one of your ancestors, and you might get even luckier!