Trinamool Congress

In the 2026 West Bengal Legislative Assembly election held in May, AITC suffered a landslide defeat, losing 135 seats and failing to secure a majority. Chief Minister Mamata Banerjee lost her own seat in Bhabanipur and initially refused to resign, claiming irregularities. She vacated office only upon dissolution of the assembly by the governor on 2026‑05‑07, marking the end of AITC’s 15‑year rule.

On 2021‑05‑02, following the state assembly elections, AITC, under Mamata Banerjee’s leadership, won a third consecutive term in West Bengal amidst an aggressive challenge from the BJP. Despite the defection of key members to rival parties, the party secured a landslide victory, reaffirming its stronghold in the state.

On 2016‑09‑02, the Election Commission of India accorded AITC the status of a national political party, following its performance in multiple states. This recognition reflected its growing influence beyond West Bengal and its emergence as a significant player on the national political stage.

On 2011‑07‑21, at the Shaheed Dibas Rally in Kolkata, AITC formally launched its youth wing, the Trinamool Youth Congress. Initially led by Abhishek Banerjee until 2021, the wing aimed to engage younger voters and strengthen grassroots activism through organized youth participation.

Between 18 April and 10 May 2011, West Bengal held legislative assembly elections. On 2011‑05‑10, AITC-led alliance secured 227 seats, ending the Left Front’s 34‑year rule. AITC alone won 184 seats, enabling governance without coalition support. Mamata Banerjee became Chief Minister, marking a watershed moment in the state’s politics.

In the 2009 Lok Sabha elections, AITC achieved a breakthrough by winning 19 seats in West Bengal as part of an alliance with the Indian National Congress. Subsequently, Mamata Banerjee joined the central government as Minister of Railways under Prime Minister Manmohan Singh, elevating the party’s influence at the national level.

In December 2006, the Nandigram crisis unfolded after the Haldia Development Authority sought to evict approximately 70,000 residents to establish a chemical plant. AITC led the resistance, forming the Bhumi Uchchhed Pratirodh Committee. On 2007‑03‑14, police firing killed 14 villagers, triggering widespread outrage and propelling AITC’s popularity as the main opposition to the CPI(M) government.

In 2000, AITC won the Kolkata Municipal Corporation elections, capturing control of the civic body governing the capital city of West Bengal. This marked the party’s growing urban appeal and its ability to translate electoral strength into administrative power at the municipal level.

In the subsequent 1999 Lok Sabha elections, AITC increased its tally by one seat, securing eight seats as part of its continued alliance with the NDA. This modest growth in representation underscored the party’s steady consolidation in West Bengal and growing relevance at the national level.

In the 1998 Lok Sabha elections held on 16, 22 and 28 February, AITC, contesting its first national poll, won seven seats. As part of the NDA alliance led by BJP, this result provided the fledgling party with a foothold at the national level and signaled its potential as an emerging political force.

On 1998‑01‑01, Mamata Banerjee, after more than 26 years in the Indian National Congress, established the All India Trinamool Congress (AITC), also known as Trinamool Congress, as a breakaway faction. She personally sketched the party’s emblem—two green shoots rising from grass—to symbolize grassroots unity and secularism. The Election Commission approved the logo on the condition that the party must secure at least six percent of the votes in the upcoming Lok Sabha election to retain it, a condition AITC subsequently met, cementing its early legitimacy.