The boundary that moved: annexation flags at the jumping censuses

1905 — 1970s

South Bend's population record warns that its line barely moved; Mishawaka's must warn of the opposite, at the four censuses where the line is inside the number: The annexation acts themselves — their ordinances, fights and reversals — are told in the Government section; here they are taken up only where they move the count, census by census.

1910 — the Great Annexation inside a +113.8 percent jump: In January 1905 the city took in 1,353 acres west of Logan Street and south of the tracks — the West End and Belgian Town, the ground of the future Merrifield Park, Mishawaka High School and Fairview Cemetery — and the boundary stood confirmed by the Indiana Supreme Court by 1908. The census of 1910 then counted 11,886 against 5,560 in 1900, a gain of 6,326. How much of that gain was the annexed thousands and how much was growth on the old ground, the record reached does not apportion: no annexed-area population for the 1905 taking stands in the sources read, and the split is named here as a gap, with the 1910 census's own ward and enumeration-district tables as its settling source. What can be stated at number size is the frame: the annexation added the city's most populous immigrant quarter — Belgian Town alone counted 568 Belgians in 1901, in a taking whose whole population was certainly in the thousands — so the 1910 jump is a boundary jump and a boom census at once, and it must never be quoted as pure growth.

1930 — Twin Branch inside a +88.4 percent jump: The Twin Branch country east of the city — the dam, the power plant, and the Penn Township settlement growing around both — was annexed in 1927, on De Kever's dating, three years before the census that recorded the city's fastest decade. (The Story of Mishawaka section and schools fragments of this record carry the Twin Branch country as "in by 1919–20," a phrasing that dates the schoolhouse, not the annexation; the Government section prints the conflict and follows De Kever's 1927, and this section follows the Government section.) The 1930 count of 28,630 is up 13,435 on 1920. Twin Branch was a plant settlement, not a subdivision — its annexed population was in the hundreds or low thousands, not the thousands the West End carried — so the 1920s jump is principally growth: the factory boom on ground mostly already inside the line, with a boundary contribution the record does not number and this section does not estimate.

1950 — Normain Heights: annexed empty, counted full: The eighty acres of farmland annexed for the veterans' subdivision — ground broken 13 November 1947, the subdivision dedicated in October 1948 — entered the city essentially empty and were counted in 1950 with the first of their 315 houses built and filling. The 1950 gain of 4,615 is therefore growth on annexed ground rather than population taken in by the line: the boundary made the growth countable as the city's, and the distinction is the entry's point. The same pattern, at commercial scale, governs the last great taking: the eighty-acre University Park Mall site of the 1970s stood more than a mile beyond the limits, South Bend declined it, and Mayor Prickett took it in with the utilities — an annexation of jobs and tax base whose residential population was nil, moving no census by itself while it moved the city's economy whole. And the one annexation that would have moved a count and did not: River Park, annexed in August 1910 and lost again on remonstrance, its people counted in South Bend's series in the end, never in Mishawaka's.

1970 — the one census that apportions itself: The 1970 census volume is the only one in the record reached that prints the boundary's arithmetic directly: of the 35,517 counted in 1970, 34,262 lived in the area the city had held at the 1960 census and 1,255 in the area annexed since — that is, of the decade's counted gain of 2,156 on the volumes' basis, well over half was people taken in by the moving line, and the old ground grew by 901. It is the standing caution for the whole table, printed at the one census where the census itself supplies it: in Mishawaka, a decade's growth figure is a compound of people and paper, and only the 1970 volume separates the two.

Sources:

1. Government section of this history — the Great Annexation of January 1905 (1,353 acres; confirmed by 1908); the River Park annexation and reversal of 1910; Twin Branch annexed 1927 (De Kever), with the Story of Mishawaka section/schools "1919–20" conflict printed there; the Normain Heights annexation and groundbreaking of 13 November 1947; the University Park Mall annexation — all cross-referenced; this entry prints only counted effects.
2. U.S. Bureau of the Census, Census of Population: 1970, Vol. I, Part 16 (Indiana) — the annexed-area accounting: 34,262 in the 1960 area, 1,255 in the annexed area, of the 35,517 counted.
3. Neighborhoods section of this history — Belgian Town's documented bounds and the count of 568 Belgians in 1901; Normain Heights' 315 houses.