I–III–IV–iv in B♭ Major
Pattern: I – III – IV – iv
Chords: B♭ – D – E♭ – Ebm
Chord Breakdown
| Numeral | Chord | Type | Function |
|---|---|---|---|
| I | B♭ (details) | major | Tonic |
| III | D (details) | major | Mediant |
| IV | E♭ (details) | major | Subdominant |
| iv | Ebm (details) | minor | Subdominant |
Harmonic Analysis
This progression moves through B♭ (Tonic) → D (Mediant) → E♭ (Subdominant) → Ebm (Subdominant).
The I–III–IV–iv progression features a chromatic ascent from I to IV via a secondary dominant III, then darkens with a borrowed minor iv. The III chord (V/vi) adds unexpected brightness while the iv creates a ♭ittersweet descent. This pattern appears in classic rock and singer-songwriter music.
Song Examples
- Something — The Beatles
- My Girl — The Temptations