FTSE 100 First Crossed 10,000 in History — Then Iran War Struck
The FTSE 100 broke through the psychologically significant 10,000-point barrier for the first time in its forty-year history in January 2026, a milestone celebrated by City commentators as validation of London’s resilience as a global financial centre. The achievement followed years in which the UK benchmark had lagged behind American and European counterparts, prompting sustained debate about the relative attractiveness of London-listed companies to international investors.
The initial crossing of 10,000 and the subsequent rally to an all-time high of 10,934 on 27 February were driven by a combination of factors: strong performances from the index’s large-cap energy and mining components, a recovery in sterling that reflected improving UK economic data, and a rotation of capital from technology-heavy American indices as valuations there came under scrutiny.
The timing of the record, however, proved to be bittersweet. Within days of the FTSE reaching its peak, the outbreak of the US-Iran conflict on 28 February 2026 injected an entirely new set of uncertainties into global markets. Although the initial oil price spike boosted the energy-heavy FTSE in the first hours of the conflict, the broader consequences — including inflation expectations, consumer spending forecasts and the disruption to global shipping — quickly reversed the gains.
For UK investors, the episode illustrated both the benefits and the limitations of the FTSE 100’s composition. The index’s high weighting towards energy, mining and international consumer goods companies makes it unusually sensitive to commodity price movements and geopolitical events, producing strong performance when raw materials are expensive but vulnerability when global growth expectations deteriorate.
Fund managers have noted that the war-period volatility accelerated a trend towards alternative UK equity exposure, with investment trusts and mid-cap funds attracting notable inflows from investors seeking less concentrated commodity risk than the FTSE 100 provides.
