I
- Ian M. Rolland — Lincoln's hometown chief Founders & CEOs
- Ice: the winter harvest that mostly happened elsewhere The Three Rivers
- Illinois Road and Jefferson Boulevard — U.S. 24's path through the west side Main Roads & Corridors
- Illsley Place and West Rudisill Neighborhoods
- In 1982 the river crested at 26.93 feet, 30,000 volunteers saved the city, and Reagan named it ‘The City That Saved Itself.’ Famous Stories & the Record
- In the Company of Men (1997): the landmark Film
- Inca Manufacturing Company Notable People
- Inca Manufacturing Company (Inca / INCA — later Phelps Dodge Magnet Wire) Businesses
- Indian Village Neighborhoods
- Indian Village Elementary School Schools & Colleges
- The Indiana History and Genealogy Room opens Libraries
- The Indiana Hotel: the theatre's hotel, 1928–1971, and its second life Hotels
- Indiana Service Corporation Businesses
- Indiana Tech Schools & Colleges
- Indiana Tech: a coach's name on the track, and the Zollner million Major Donations
- Indiana University Fort Wayne Schools & Colleges
- The Indianapolis roster: Fort Wayne's honest line Racing
- The industrial city that did not distill Wineries & Distilleries
- Industrial Revolution Section
- Influencers & Digital Creators Section
- The infrastructure: a library resource center, a fundraisers' chapter, an alliance Foundations & Nonprofits
- The institutional table: school lunch at city scale Food & Restaurants
- The institutions: bureau, co-op, extension, 4-H Farms & Crops
- The insurance orders: Woodmen, Maccabees, and the benefit machine Lodges & Fraternal Orders
- Intercity buses — Greyhound, Trailways and the depots Public Transit
- International Business College Schools & Colleges
- International Harvester — Fort Wayne Works Businesses
- International Harvester — Fort Wayne Works Notable People
- The International Harvester Plant (1923–1983) — the Heavy-Duty Truck Capital Architecture
- International Leadership School Schools & Colleges
- "International": the customs station and the name, 1988–1991 Airports
- The interurban web — electric cars to everywhere Railroads
- Inventors & Inventions Section
- The IRS Form 990 series Sources
- Irving Rifkin — scrap from a truck Founders & CEOs
- Isaac M. Rosenthal, M.D. Notable People
- Isaac McCoy's mission church, and the First Baptist line Churches & Religion
- Islam in Fort Wayne: the Islamic Center and Masjid Al-Quds Churches & Religion
- ITT in Fort Wayne — the Farnsworth succession to L3Harris Businesses
- ITT's radios — SINCGARS and the tactical-communications works Technology
- Ivy Tech Fort Wayne Schools & Colleges