Grant County was formed from Umatilla and Wasco counties in 1864.
1850 Grant County, Oregon Census
- Free 1850 Census Form for your Research
- Free 1850 Census Images (partially indexed)
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- Hosted at Census Guide
1860 Grant County, Oregon Census
- Free 1860 Census Form for your Research
- Free 1860 Census Images and Index
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- Hosted at Census Guide
1870 Grant County, Oregon Census
- Free 1870 Census Form for your Research
- Free 1870 Census Images and Index
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- Free 1870 Census Index
- Free 1870 Census Transcription
- Hosted at Census Guide
1880 Grant County, Oregon Census
- Free 1880 Census Form for your Research
- Free 1880 Census Transcription
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- Hosted at Census Guide
1890 Grant County, Oregon Census
- Free 1890 Census Form for your Research
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- Hosted at Census Guide
1900 Grant County, Oregon Census
- Free 1900 Census Form for your Research
- Free 1900 Census Images and Index
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- Hosted at Census Guide
1910 Grant County, Oregon Census
- Free 1910 Census Form for your Research
- Hosted at Ancestry.com – Ancestry Free Trial
- Hosted at Census Guide
1920 Grant County, Oregon Census
- Free 1920 Census Form for your Research
- Free 1920 Census Images and Index (partial)
- Hosted at Ancestry.com – Ancestry Free Trial
- Hosted at Census Guide
1930 Grant County, Oregon Census
- Free 1930 Census Form for your Research
- Hosted at Ancestry.com – Ancestry Free Trial
- Hosted at Census Guide