This review summarizes climate changes over the past several millennia, focusing on the last 1-2 millennia. It evaluates proxy-based reconstructions and climate modeling studies to assess past climate trends, particularly temperature patterns. The study confirms that the late 20th century warmth was unprecedented at hemispheric and likely global scales. While some climate variability modes, such as ENSO and NAO, may have shown anomalous behavior in the late 20th century, regional conclusions are less certain, especially in the Southern Hemisphere and tropics. The use of terms like "Little Ice Age" and "Medieval Warm Period" is limited due to the difficulty in accurately describing past climate epochs. Natural factors explain major surface temperature changes up to the 19th century, but anthropogenic forcing explains recent warming. Proxy data, including tree rings, coral records, ice cores, and speleothems, provide insights into past climate variability. Instrumental data are limited to the past 150 years, but reconstructions using proxy data and climate models help understand longer-term trends. The study highlights the importance of combining proxy data with climate models to better understand past climate changes and their implications for future climate.This review summarizes climate changes over the past several millennia, focusing on the last 1-2 millennia. It evaluates proxy-based reconstructions and climate modeling studies to assess past climate trends, particularly temperature patterns. The study confirms that the late 20th century warmth was unprecedented at hemispheric and likely global scales. While some climate variability modes, such as ENSO and NAO, may have shown anomalous behavior in the late 20th century, regional conclusions are less certain, especially in the Southern Hemisphere and tropics. The use of terms like "Little Ice Age" and "Medieval Warm Period" is limited due to the difficulty in accurately describing past climate epochs. Natural factors explain major surface temperature changes up to the 19th century, but anthropogenic forcing explains recent warming. Proxy data, including tree rings, coral records, ice cores, and speleothems, provide insights into past climate variability. Instrumental data are limited to the past 150 years, but reconstructions using proxy data and climate models help understand longer-term trends. The study highlights the importance of combining proxy data with climate models to better understand past climate changes and their implications for future climate.