Lahore is the capital city of the Pakistani province of Punjab. It is the second-most populous city in Pakistan after Karachi. The city is located in the north-eastern end of Pakistan's Punjab province, near the border with the Indian state of Punjab. Lahore is the historic cultural centre of the Punjab region, and is the largest Punjabi city in the world. The city has a long history, and was once under the rule of the Hindu Shahis, Ghaznavids, Ghurids, and the Delhi Sultanate. Lahore reached the height of its splendour under the Mughal Empire, serving as its capital city for a number of years. The city was captured by the forces of Persian Afsharid Emperor Nader Shah during his invasion of the Mughal Empire. The city was then contested between different powers before it became capital of the Sikh Empire, and then the capital of the Punjab under British rule. Lahore was central to the independence movements of both India and Pakistan, with the city being the site of both the declaration of Indian Independence, and the resolution calling for the establishment of Pakistan. Following the independence of Pakistan in 1947, Lahore became the capital of Pakistan's Punjab province. Lahore has a semi-arid climate. The hottest month is June, when average highs routinely exceed 40 °C (104.0 °F). The monsoon season starts in late June, and the wettest month is July, with heavy rainfalls and evening thunderstorms with the possibility of cloudbursts. The coolest month is January with dense fog.