Table:
0
A
B
C
D
E
1
District
Vacator
Reason for change
Successor
Date successor seated
2
Colorado Territory At-large
New seat
New seat
Hiram P. Bennett (Conservative R)
August 19, 1861
3
Nevada Territory At-large
New seat
New seat
John Cradlebaugh
December 2, 1861
4
Dakota Territory At-large
New seat
New seat
John B. S. Todd (D)
December 9, 1861
5
Louisiana 1st
Vacant
Vacant
Benjamin F. Flanders (U)
December 3, 1862
6
Louisiana 2nd
Vacant
Vacant
Michael Hahn (U)
December 3, 1862
7
Virginia 1st
Vacant
Vacant
Joseph E. Segar (U)
May 6, 1862
8
Virginia 7th
Vacant
Vacant
Charles H. Upton (U)
July 4, 1861
9
Ohio 13th
John Sherman (R)
Resigned March 12, 1861 when elected U.S. Senator
Samuel T. Worcester (R)
July 4, 1861
10
Pennsylvania 12th
George W. Scranton (R)
Died March 24, 1861
Hendrick B. Wright (D)
July 4, 1861
11
Oregon At-large
Andrew J. Thayer (D)
Election was successfully contested July 30, 1861
George K. Shiel (D)
July 30, 1861
12
Massachusetts 5th
William Appleton (CU)
Resigned September 27, 1861 due to failing health
Samuel Hooper (R)
December 2, 1861
13
Kentucky 1st
Henry C. Burnett (D)
Expelled December 3, 1861 for support of secession
Samuel L. Casey (U)
March 10, 1862
14
Kentucky 2nd
James S. Jackson (U)
Resigned December 13, 1861 to enter the Union Army
George H. Yeaman (U)
December 1, 1862
15
Virginia 7th
Charles H. Upton (U)
Declared not entitled to seat February 27, 1862
Lewis McKenzie (U)
February 16, 1863
16
Illinois 9th
John A. Logan (D)
Resigned April 2, 1862 to enter the Union Army
William J. Allen (D)
June 2, 1862
17
Pennsylvania 7th
Thomas B. Cooper (D)
Died April 4, 1862
John D. Stiles (D)
June 3, 1862
18
Massachusetts 9th
Goldsmith F. Bailey (R)
Died May 8, 1862
Amasa Walker (R)
December 1, 1862
19
Missouri 1st
Francis P. Blair, Jr. (R)
Resigned July 1862 to become colonel in Union Army
Vacant
Vacant for remainder of term

Questions and formulas:
Question: Name the date successor seated for successor being vacant
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,D1="Vacant"),5))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E19,D2:D19="Vacant"),5))
Level: medium
Question: Name the vacator for kentucky 2nd
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,A1="Kentucky 2nd"),2))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E19,A2:A19="Kentucky 2nd"),2))
Level: medium
Question: Name the successor for election was successfully contested july 30, 1861
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,C1="Election was successfully contested July 30, 1861"),4))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E19,C2:C19="Election was successfully contested July 30, 1861"),4))
Level: medium
Question: Name the successor for vacant and december 3, 1862
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,(C1="Vacant")*(E1="December 3, 1862")),4))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E19,(C2:C19="Vacant")*(E2:E19="December 3, 1862")),4))
Level: medium