1.  Indiana Marriage Index, 1845-1920 (online at Ancestry.com):

Groom / Bride	Age	Date	County	Book
William Swope	16	5 Jul 1879	Marion	73
Mary A Stewart	16

William and Mary should be 26 and 25, respectively, not 16.  This has to be some kind of data-entry error.

2.  1870 Census Every-Name-Index/Images (online at Ancestry.com, Image #27 of 147):  Indianapolis P.O., Indianapolis (Ward 3), Marion Co., IN, Roll M593_340, p. 121A, PN 27, 195/198, enumerated 15 Jun 1870, official enumeration date 1 Jun 1870 (extracted by Diana Gale Matthiesen):

Swope Elizabeth	41	F	W	Seamstress			Ohio
_____ William	17	M	W	Wks Stove Factory			Ind
_____ Albert C	12	M	W	At Home			"

3.  1880 Census Every-Name-Index/Images (online at Ancestry.com, Image #36 of 62):  Indianapolis, Marion Co., IN, Roll T9_295, p. 153A, PN 37, SD 3, ED 111, enumerated 9 Jun 1880, official enumeration date 1 Jun 1880 (extracted by Diana Gale Matthiesen):

1880:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).
		1	2	3	4	5	6	8	10	12	13	24	25	26
*	570	284	299	Schwaub William	W	M	26	Father	/		Works Stove Factory	IN	IN	Ire?
				_______ Mary	W	F	24	Wife	/	/	Keeping House	OH	OH	OH
*

They are sharing a dwelling with the MUELLER family from Wuerttemberg, and if one of the MUELLER's was the informant, it could it explain why the original German spelling was used — SWOPE is an Anglicized spelling of SCHWAB.

4.  1890 Census:  the 1890 Census Population Schedules were destroyed.

5.  1900 Census Every-Name-Index/Images (online at Ancestry.com, Image #3 of 21):  1218 W. Market St., Indianapolis City (Ward 5), Centre Twp., Marion Co., IN, Roll T623_388 (Book 2), p. 30A, SN 2, SD 7, Ed 79, enumerated 1 Jun 1900, official enumeration date 1 Jun 1900 (extracted by Diana Gale Matthiesen):¤

1900:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).
		1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	19	20	21	22	23	24	25	27
*	1218	29	32	Swope William	Head	W	M	Jan 1854	46	M	21			IN	IN	IN	Day laborer	5		Y	Y	Y	R	H
				_____ Mary	Wife	W	F	Oct 1854	45	M	21	0	0	MD	Ire	Ire				Y	Y	Y
				Strub Cora	Niece	W	F	Feb 1885	15	S				IN	IN	IN			0	Y	Y	Y
*W Market St

6.  1910 Census Index/Images (online at Ancestry.com, Image #1 of 15):  1218 Market St., Indianapolis (Ward 15), Center Twp., Marion Co., IN, Roll T624_369 (Part 3), p. 41A, SN 1A, SD 7, ED 255, enumerated 15 Apr 1910, official enumeration date 15 Apr 1910 (extracted by Diana Gale Matthiesen):

1910:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).
		1	2	3	4	5	6	7	8	9	10	11	12	13	14	17	18	19	20	21	22	23	24	25	26	28
*	1218	9	9	Swope William	Head	M	W	56	M1	30			Indiana	Ohio	Indiana	Eng	laborer	planing mill	W	N	0	Y	Y		R	H
				_____ Mary	Wife	F	W	55	M1	30	0	0	Maryland	Ire-English	Ire-English	Eng	none					Y	Y
				Hardee James	Grand-nephew	M	W	8	S				Indiana	Indiana	Indiana		none							Y
*Market St

7.  1920 Census Index/Images (online at Ancestry.com, Image #6 of 22):  1628 W Market St., Indianapolis City (Ward 15), Center Twp., Marion Co., IN, Roll T625_456, p. 47B, SN 3B, SD 7, ED 255, enumerated 2/3 Jan 1920, official enumeration date 1 Jan 1920 (extracted by Diana Gale Matthiesen):

1920:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).

1

2

3

4

5

6

7

9

10

11

12

16

17

18

19

21

22

23

24

25

26

27

28

*

1628

57

67

Swope William

Head

R

M

W

66

M

Y

Y

IN

OH

OH

Y

Laborer

Lumber Yard

W

_____ Mary

Wife

F

W

64

M

Y

N

MD

Ire

Eng

Ire

Eng

Y

None

Hardy James

Nephew

M

W

18

M

N

Y

Y

IN

OH

IN

Y

Laborer

Foundry

W

_____ Lorain

Niece

F

W

17

M

N

Y

Y

IN

IN

IN

Y

None

*W Market St

8.  1930 Census Index/Images (online at Ancestry.com):  not found, but I can't say my search was exhaustive.

9.  Messages posted to the STRUB Surname Board (online at RootsWeb.com/Ancestry.com).