The charity that cares for historic Shakespeare sites in Stratford-upon-Avon has received an unprecedented donation of £1m from the Olivier award-winning US playwright Ken Ludwig. The Shakespeare Birthplace Trust (SBT) can now pay for crucial conservation work on Hall’s Croft, the home of Shakespeare’s daughter Susanna and her physician husband, John Hall, who is believed to have advised his father-in-law on medical matters. It is the largest private donation in the trust’s 177-year history. Ludwig has had a lifelong passion for Shakespeare. He told the Guardian that, while on a visit to Stratford, he felt he had to help after hearing of the building’s plight while being shown round by Charlotte Scott, one of SBT’s directors: “They were asking themselves: ‘How can we save Hall’s Croft because it’s literally falling over?’ I said to them, ‘What would it cost to save it?’ They told me and, I thought, if there’s any time I can make a difference about the things I care about, this is it. So I just said: ‘I’ll do it.’” This is his first substantial donation: “It’s what’s needed right now to keep the place upright.” Hall’s Croft, one of the last complete examples of Jacobean architecture, dates back to 1613. But steel girders installed in the last century to support the roof are sinking into the ground. An extension added in the 17th century is pulling away from the original house, so the two parts are leaning in different directions. Scott recalled showing Ludwig the huge metal girders “holding the house up” and found herself being astonished by his “extraordinary generosity and philanthropy”, which will ensure Hall’s Croft’s survival. “It is one of the most unique examples of middle-class 17th-century living in the country,” she said. “It holds a spectacular range of 17th-century furniture, second only to the Victoria and Albert Museum.” Lena Cowen Orlin, SBT’s vice-chair and emeritus professor of English at Georgetown University in the US, said: “Hall’s Croft is a beautiful and atmospheric building that has been suffering from the need for serious intervention. Now we have the angel to make this possible … It’s a sleeping beauty of a building and Ken Ludwig is helping the trust bring it back to life as Shakespeare and his family knew it.” The SBT, an independent charity, oversees five historic Shakespeare family homes: Shakespeare’s Birthplace, Shakespeare’s New Place, Anne Hathaway’s Cottage, Mary Arden’s Farm and Hall’s Croft. Orlin said they all told women’s stories: “That of his mother survives at Mary Arden’s Farm. His wife grew up in Anne Hathaway’s Cottage … We associate Susanna mostly with Hall’s Croft, a uniquely evocative survival of the status the Shakespeares achieved. It is a warm and generous family home, a beautiful and atmospheric building. The timing of this gift is brilliant. The SBT has embarked on a three-year arc of research and programming devoted to ‘the women who made Shakespeare’.” Ludwig’s 34 plays and musicals have been performed in 30 countries. His commissions have come from the Agatha Christie estate and the Royal Shakespeare Company, among others. His first play, Lend Me a Tenor, won two Tony awards and was described by the Washington Post as “one of the classic comedies of the 20th century”. Among his subsequent productions, Crazy For You was on Broadway for five years and in the West End for three, winning Tony and Olivier awards for best musical. His stage adaptation of Christie’s Murder on the Orient Express begins a 25-city tour of the UK and Ireland on 6 September. He said: “I’ve always loved Shakespeare, the ultimate genius. As a writer, I fell in love with the recordings of Richard Burton. I listened to his Hamlet, the one that John Gielgud directed, so many times. Shakespeare became the centre of my life. I wrote a book about Shakespeare and I’ve written three plays somehow involving him [including Shakespeare in Hollywood, commissioned by the RSC]. Then, in every play I’ve written, there’s always some quotation from Shakespeare. It became a signature of mine.” Asked about the emotion he feels on walking into Hall’s Croft, he said: “A shiver of intellectual joy. It feels like a personal connection with Shakespeare. It also has the most beautiful garden I’ve ever seen.” Hall had used its plants with medicinal properties to treat his patients, perhaps also inspiring his father-in-law, whose plays reflect his understanding of the magical powers of herbs and flowers. Ludwig said that Hall’s Croft had stood for more than 400 years: “I can’t think of any project more worthwhile than partnering with the SBT to ensure that it stands for the next 400.”