Ion Dragoumis studied law at Athens University and, in 1899, entered the diplomatic branch of the Greek Foreign Ministry.
During this period, he also toyed with the idea of a Greek-Ottoman Empire, believing that Greeks, already having control of commerce and finance, would also gain political power in such an arrangement.
In 1910 he founded, collaborating with philologists and writers (Vlasis Gavriilidis, Nikos Kazantzakis, Alexandros Delmouzos, Alexandros Papanastasiou, Manolis Triantafyllidis, Lorentzos Mavilis), the Educational Club (Εκπαιδευτικός Όμιλος), an organization for the promotion of Demotic Greek language, while he was writing also articles in the philological magazine "Noumas" (with the nickname Idas).
With the outbreak of the First World War, he was in favour of Greece joining the Entente, but gradually and during the National Schism he disagreed with Venizelos' policy and became hostile towards Venizelists.
On 30 July 1920 an attempt was made by two royalists to assassinate Venizelos at the Gare de Lyon railway station in Paris.
The next day, 31 July, Dragoumis was stopped by a Venizelist Democratic Security Battalion (Δημοκρατικά Τάγματα Ασφαλείας) in Athens and was executed as a form of payback.
Though her relationship with him ended many years before, Penelope Delta (herself a supporter of Venizelos) deeply mourned Dragoumis, and after he was killed wore nothing but black until her own death two decades later.